Dig into all of the veggies and cheesy goodness that you could ask for!
Casseroles are typically thought of as high-calorie comfort food, but this slimmed-down vegetarian dish is about to change that. Our baked zucchini, spinach, and feta casserole uses fresh and healthy ingredients that come together in under an hour to create a seriously tasty main meal or side dish! And because this recipe pairs some of the best ingredients of the summer with the warmth and comfort of a casserole, it’s a wonderful meal to serve any day of the year!
A Hassle-Free Casserole
One of the major reasons that we love casseroles– aside from the fact that they’re delicious– is because they’re usually incredibly easy to prepare. Our baked zucchini, spinach, and feta casserole is both of those things and more! This recipe is perfect for beginners because the steps are easy to follow, but flavorful enough that it will grab the attention of even the most seasoned chefs.
Let the oven preheat to 400 degrees while you cook the veggies. Heat some olive oil in a large skillet. Once it’s hot, add the spinach, zucchini, and yellow squash to the pan. Cook this veggie mixture for about 5 minutes, until the spinach is wilted and the squash is soft. Drain any excess liquid and place the veggies in a large mixing bowl.
Next, add the feta, parmesan, breadcrumbs, egg whites, garlic powder, dried basil leaves, and salt and pepper to the mixing bowl with the veggie mixture. Fold the ingredients together until they’re evenly combined and then spread the mixture in an even layer in your prepared casserole dish. Bake for 30 to 40 minutes or until the top of the casserole is a beautiful golden brown. Let it cool for a few minutes before serving!
Healthy, Cheesy, and Delicious!
This easy casserole packs a hearty dose of veggies, while simultaneously boasting all of the cheesy goodness you look for in a casserole.
Oftentimes, veggies are thought of simply as a means to fill you up while keeping calories low. While the fibrous volume of vegetables is great at doing this, the taste and texture is also a reason to include them in all of your meals! The two stars of this show are spinach and zucchini. Not only are these two ingredients delicious, but they also happen to be some of the healthiest veggies around.
Spinach offers many different vitamins and minerals, but there are a few that stand out. It contains more potassium than bananas, a mineral that is essential for heart health and muscle function. It is also rich in magnesium, which is another mineral that regulates muscle and nerve function, as well as blood pressure.
Zucchini is another veggie that contains a wide range of nutrients, but vitamin A is one of the most prevalent. This vitamin is important for vision and immune health!
And we can’t forget about the cheese! No casserole is complete without it. We decided to go with fat-free feta and low-fat parmesan, in order to cut some calories but not compromise on flavor. Whole-wheat bread crumbs also help to keep things a little bit healthier.
Serving Our Baked Zucchini, Spinach, and Feta Casserole
Like we said, this casserole can be used as a main course or as a side dish! If you choose to make it as a side, but need some ideas for a main course, we can help! It will pair wonderfully with any of these main dish options:
Baked Zucchini, Spinach, and Feta Casserole
- 2 tablespoons olive oil
- 3 cups baby spinach
- 2 zucchini small, diced small
- 2 yellow squash small, diced small, OR 2 more zucchini if yellow squash is unavailable.
- 1/4 cup feta cheese crumbles fat-free
- 1/4 cup parmesan cheese low-fat, grated
- 1/4 cup whole-wheat panko breadcrumbs
- 2 egg whites
- 1/2 teaspoon kosher salt
- 2 teaspoons garlic powder
- 1/2 teaspoon ground black pepper
- 1 teaspoon dried basil leaves
- Preheat the oven to 400 degrees. Spray a 9 x 13 inch casserole dish with non-stick spray and set aside.
- In a large skillet, heat the olive oil. Once hot, add the spinach, zucchini, and yellow squash. Cook, about 5 minutes, until the spinach is wilted and squash is soft. Drain off any excess liquid and place in a large mixing bowl.
- Add the remaining ingredients to mixing bowl with the spinach mix. Combine well and spread the mixture in an even layer in the prepared casserole dish. Bake for 30 to 40 minutes or until golden brown on top. Let cool slightly before serving.
Have you made this recipe?
Tag @skinnyms on Instagram or hashtag it #skinnyms
If you give this Baked Zucchini, Spinach, and Feta Casserole a try, we would love to hear what you thought about it in the comment section!
Follow us on Pinterest and check out our Facebook for more healthy eating tips, tricks, and recipes!
When you say package spinach, I am not sure what that means. Loose raw spinach leaves, or something chopped and frozen?
Tori, Just tweaked to “baby spinach”. I’m not a big fan of frozen spinach, too much time sqeezing all that water out. When available, fresh is best. 🙂
Just made casserole for dinner tonight and it was delicious! Very easy and such a great way to use summer veggies! Family said this recipe was a keeper. Thank you for sharing.
I am a little confused about the serving size. If this is is made in a 9×13 pan and makes 6 servings, then each serving has to be more than a 1/2 cup. Maybe should it be 16 servings?
Donna, It’s actually 1 cup serving size, which was just updated. Thanks so much for your comment. 🙂
I didn’t have zucchini or yellow squash so I used vegetables I had on hand red peppers, artichoke hearts asparagus sautéed with spinach used the entire tub of spinach jus two of us. Recipe calls for 3 cups spinach. Followed the recipe and it was absolutely delicious! Next time I go to organic market I’ll get the squash I need.
Rhonda, Thank you for the feedback. Please leave a review when you have a minute.
I’m assuming “1/4 whole wheat panko bread crumbs” means 1/4 Cup – is that right?
Dee, Yes 1/4 cup. Just added “cup”. Thanks so much. 🙂
Any chance for a GF modification?
Juliana, Simply use GF panko.
Can this be frozen?
Monique, Sure can. Just be sure to defrosting in the fridge.
Could this be “baked” in the crockpot? It’s so hot in the summer that I dread using the oven and thought putting all this in the crockpot might be an option.
Michelle, Sure, you can make in the slow cooker. You might enjoy this recipe.
Delish!! The ONLY reason I did not give this 5 stars is because I tweaked it, so I can’t speak to the original. I added crushed red pepper to the olive oil that I sauteed the zucchini in – no yellow squash, because I didn’t have any. I increased the baby spinach because why not, used one whole egg and one egg white. Subbed Greek seasoning for the garlic powder and basil and omitted the kosher salt. Baked in a 7×11 pan and it absolutely made 6 side dish servings for Greek yogurt marinated grilled chicken and orzo. This one is officially in rotation.
With the feta and parmesan I’m concerned this would be very salty. Would different cheese work as well, such as cheddar or provolone?
Hi Helen, yes you can substitute cheddar or provolone. However, I would try this recipe by leaving out the Kosher salt and leaving the feta and parmesan. You can also reduce the amount of feta and parmesan, each of these cheeses have a distinct flavor that pairs very well with zucchini and spinach!
I think the per serving carb count is off. The only thing in this recipe that has significant carbs is the Panko, which is around 11 carbs for 1/4 cup. Should the carb count be more like 3 or 4 per serving?
Hi Jen, thanks for your question. I double checked the recipe and the carb count is correct. Zucchini and yellow squash both contain carbohydrates which make the carb count higher. Believe it or not, a single serving of yellow squash contains quite a lot of carbohydrates!
I add cooked pasta to mine before baking for a more complete main dish and it’s delicious!
One cup of yellow/summer squash is 3-4 net carbs, depending on the source you go by. It’s on every low carb veggie list too. I’m still not seeing where you are coming up with 20 carbs per serving, using 2 small yellow/summer squash in this recipe.
Hi Jen, thank you for your concern. We use a professional nutritional calculator for all our recipes and have checked this recipe numerous times and come up with the same 20g carbohydrate count.
Can you substitute the vegetables? If so what combination would you suggest? Not a fan of zucchini:)
Sheila, Yellow squash would work well.
It’s got to be 3 cups cooked spinach because I made it with fresh spinach and only 3 cups fresh spinach and it was super thin, not like the picture .
Hi Jennifer, this recipe uses baby spinach. In our recipes we will specify if the spinach is cooked ie: 1 cup cooked spinach versus 1 cup baby spinach. Hope this helps!
I’m a bit confused. If I had made this in a 9X13 pan I don’t think it would have hardly covered the bottom. And if I baked it 30+ minutes it would have been crispy. It’s barely 6 servings in a 10X7 pan and not very thick.
How long you think will last in fridge? Would this freeze well?
Cary, It should last a few days in the fridge. Yes, it does freeze well. Just be sure to thaw in the fridge.
Is there anything that I can substitute eggs? I’m allergic to eggs but would love to try recipe.
You can leave the eggs out of this recipe. Instead, add about 1/4 cup shredded mozzarella cheese and 1 tablespoon of flour. This will help bind the ingredients together the way the eggs would.
What about eggplant instead of zucchini? Curious since I have it in the house.
Absolutely! Let us know how you like the finished recipe. Have a great day!
I made this last night and it is our favorite dish yet!! It only made 4 serving between me, my boyfriend, and his guy friend. l only used 10 oz of Spinach and one medium sized Squash, but I added a little extra cheese and seasonings. I only had Panko Japanese Style breadcrumbs to use, but it still tastes amazing, and I also added crispy fried onions on top before baking just for an extra crispy zing. I think it made it 10 times better! Thank you for this mouth watering recipe, I’ll be making it again tonight for my boyfriends mom!
Chelsea, Thank you so much for the feedback. We’re thrilled you all enjoyed the casserole. 🙂
9×13 has to be wrong this is the tinyiest dish I’ve ever made 🙁 it barely filled a 8×8
Hi Amy, you can double the recipe if you’d like! This recipe is meant to be a side dish.
Very true. I’d have to triple this to serve 6-8 people. I luckily put it in a bit smaller pan b/c I was going to used another Pan and share with my sister. Well, that didn’t happen.
Is there a substitute for cooked spinach? PTSD with cooked spinach from childhood. ?
Kale would work!
Doubled and subbed kale for spinach. Delicious!
I’m not a fan of yello squash. Should I just leave it out or substitute something else for it?
Christine, I would recommend adding more zucchini.
In order to be a little more keto friendly – what could I use instead of panko bread crumbs? Crushed pork rinds? Another suggestion? Also – you mentioned in previous comments it’s meant to be a side dish – but I was thinking I could add cooked diced chicken (or shredded rotisserie chicken) and make it a meal. Thought?
Pork rinds would be delicious! Adding the chicken to make this an entree would also be a great option!
I think I’m missing something. In the picture the Panko crumbs look like they are on top of the casserole. In the instructions it mentions nothing about this, just to simply mix all remaining ingredients and bake. Do you mix the beard crumbs in the casserole or on top?
Hi Jane, the panko crumbs are not sprinkled over top. The top of the casserole with become brown and crispy, which is probably what you’re seeing.
Just signed up for the emails to get delicious dishes that are WW workable. Looking forward to trying and sharing this dish with family and friends.
Thanks for signing up, Diana! We hope you love the recipes!
Can I omit the eggs? And if so, should I replace with something?
Sonia, Yes, feel free to omit the egg.
I feel silly but, do I skin the zucchini? It’s from my garden and it’s big
Ellie, I typically skin the zucchini.
I made this for the first time tonight. It barely filled a small casserole, let alone a 9×13 baking dish. I used a 6×8 and it was perfect. Everyone LOVED the casserole–very good flavor! I used two medium zucchini, two small yellow squash, and a small bag of fresh spinach. It’s good, mostly healthy, and easy. If you’re cooking for more than 4 people, double the recipe.
We’re so glad to hear you loved the recipe!
I love your recipes and am making this my third time in the past month! I am subbing cauliflower for yellow squash. I am sure it will be as amazing. Thanks for all the great recipes and tips!!
We’re so glad to hear you love the recipes! Let us know how your substitution turns out!
Hello! Thank you SO much for sharing this recipe! It was delicious last year and making again this year! Would you be able to make ahead the day before and keep in fridge until ready to bake? Just curious! Thanks again!
Allison, Sure that would work just fine.
I’d add some sauted leek to add another flavor!
Oh great idea, Susan! We like it 🙂
Loved this. Left out salt. Used zucchini and squash noodles cut up. Increased cheese to 1/2 cup each. Do you have other recipes along the same lines?
Glad you loved the recipe, Sonia! You can search “casseroles” on our page to find many more similar recipes.
Hi. Silly question but grated parmesan like the freshly grated that you would sprinkle on top of a dish? Or shredded like the thicker longer sheds?
Grated Parmesan is the very fine almost powder type. Shredded Parmesan will also work for this recipe.
Very nice side dish for all that surplus zucchini! I added a small finely chopped onion to soften in the pan with the zucchini and squash. Will definitely add to my stock of zucchini recipes!
Awesome, Fran! We’re glad you enjoyed it 🙂
I made a double batch and added 3 chicken breasts cut in 1” chunks and sautéed with 1/2 a chopped red onion. Cooked first, set aside, used same pan for the Vegs then just combined all as described. Main dish!
Great idea, Jodi! Sounds Tasty 😀
I followed the recipe exactly and although it tasted fine it was not as cheesy as portrayed. I have liked many of the recipes on this website but was disappointed in this one. I double checked the recipe ingredients when it was done to see if any ingredients were left out but sadly none were.
Hi Marsha, feel free to adjust to your personal preferences.
Could I freeze this dish (in casserole pan) to be cooked later? I like to meal prep for the week.
You could try to freeze this, however cooked squash does not always freeze well. Instead of cooking the squash and spinach completely before adding to the casserole dish, slightly under cook the squash. This hsould help!
This is a very versatile recipe. I made it as written a couple times, and then I needed to use up some ends in my fridge. I am writing this during the COV do you 19 shelter in place time frame. I substituted the ends of some harder textured cheeses grated for the feta. I also doubled the amount of Jesus. I used whole eggs, again because we’re being frugal during this shelter in place, and frankly we need the protein. I rehydrated some minced onion with the eggs – like a tablespoon. I sliced up some greens of green onions and sauté those with the spinach. Are used regular old sprouted whole-grain bread toasted bread combs Because that’s what was in the house. Honestly. It tasted wonderful. Served with grilled ham steaks and fresh pineapple.
Thank you for the tips, Shelby! Using what you have was a great idea!
Loved this comment!! Doubling the amount of Jesus is always recommended!!??? You also answered my can you use the whole egg question.
Can I peel the squash and zucchini?
Yes, if that is your preference feel free to peel!
Would adding artichokes taste good?
Artichokes sound delicious – give it a try and let us know how it turns out!
I am making this right now and it smells amazing! Thanks for sharing!
Can I use regular breadcrumbs instead of panko?
Yes, however it will not be as crispy or crunchy.
Loved this quick and easy recipe!! I doubled the amount of feta and topped with shredded mozzarella (I love a cheesy casserole!) and it came out delicious.
You put up with a lot of criticism!! I just want you to know it was perfectly delicious!! Thank you!
Thank you, Marcie! We’re glad to hear that you enjoyed it 🙂
It’s as if no one has ever cooked! Kudos to you ladies and you incredibly positive attitudes. Love it. Great recipe!! Thank you!!
Patrick, Thank you so much for the feedback, much appreciated. 🙂
The recipe was tasty, for sure. But the ingredients and directions need to be adjusted. I know, I have read all of the posts. But a 9 X 13 pan is WAY too big for this recipe, even the way I made it.
I used about 6 cups of fresh baby spinach and it was not close to enough spinach. I would suggest using at least 10 cups of baby spinach and then put this into a 2 1/2 or 3 quart round casserole dish. Don’t get me wrong, the recipe was quite tasty. Just some helpful suggestions.
Thanks for the suggestions, Tony!
This was terrific. I had average sized zucchini and yellow squash, but I did add 1 more cup of bably spinach so that there was more of a balance. Added 1 sliced leed and also nearly doubled both cheeses. I used the whole egg, not just the whites and substituted pork panko. It fit perfectly in my 9 x 13. Delicious. Thanks!
Efranz, Sounds great. Thank you for the additional suggestions. 🙂
Made this tonight and got rave reviews. Added onion, red pepper and extra spinach. Used two whole eggs and just a bit more cheese. To bake I put it all back in skillet I used to cook veggies. It got nice little crust on bottom and was great. Will definitely make again. Lots of ways to personalize.
Kathy, Thank you for the feedback and tips. 🙂
I made a few adjustments. I added a leek because I happened to have one, I added sauteed mushrooms for a little more texture/flavor, I was out of dried basil so I used herbs de Provence. This was an awesome dinner! Definitely making again… May be as a side for a potluck
Great tips! I’m so happy you enjoyed the casserole. 🙂
So excited to try this out and use my yellow and zucchini from our garden. I’m making this for a bday party tomorrow. If I put it together now think I should bake it now and just reheat tomorrow or can I put it in the fridge without baking and bake it tomorrow?
Kim, Definitely! I do that all the time. 🙂
I made this recipe, and loved it! Thanks so much!
Great! Thank you Terri.
This was awesome!! I doubled the recipe as written, sooooo many compliments!! Thank you ?
Kathy, Great! Thank you for the feedback.
Is there a way to add some pasta, like orzo? Would the 30-40 minute cooking time be too much?
Jordan, Orzo is a good addition. Orzo typically cooks within 7-10 minutes. You might want to cook orzo and add as a side instead of cooking with the casserole.
I made this for the third time. This time I had friends over so I doubled the recipe. They all loved, loved, loved it. Super easy to make and very tasty. Thank you!
Benita, Oh WOW, that’s great feedback. Don’t you just love when guests also loves the food? 🙂
I am following a low carb, low fat, low cal diet. Can I leave the breadcrumbs out to make it a little more healthy? If I wanted to add chicken to increase the protein, would any of the cooking times changes?
If you add chicken, I recommend cutting it up into bite size pieces. If you do this, the cooking time shouldn’t change. I haven’t made this recipe without breadcrumbs so I can’t say for certain how it will turn out. Please let us know if you do and the results. 🙂
Is there a way to make this a day ahead of time, refrigerate, and then bake the following day?
Melissa, That should work fine. 🙂
Can I make this in advance and freeze it?
Katie, Sure can!
Hello! I’m trying to count calories, so wouldn’t 162kcal be 162 kilocalories which converts to 162,000 calories? Thank you for the clarification!
Helen, I’m not sure why it is showing as kcal. The actual Kcal for this recipe is 0.162. Imperial calories are 162.
Second time I made this. This recipe is definitely a keeper. Added onion and a bit if mushroom. Sliced the zucchini very thin. Added 4 whole eggs. Et viola… delicious.
I’m so happy you enjoyed the Casserole! Please leave a review if you have a moment. Thanks for the feedback.
This is a keeper!!!
Very yummy, exceeded my expectations! I also added onions and tomatoes and I think it really made it!
This recipe showed up in an email of suggested Pinterest pins, but the link was wrong — it went to ‘our three peas’ and the recipe is not shared on that site (at least, not that I can find, since it does not have a search feature). I finally noticed the fine print in the picture with your site. Hope this helps!
Thank you so much for the heads up. We’ll take a look. 🙂
This was super easy to make and one of the best zucchini dishes I’ve ever had ! Recommend it 100%
Thank you so much for the feedback. Please leave a review when you have a minute.
This is why 5 star reviews were created. My husband and I looked at each other after the first bite didn’t have to say anything because we both had love in our eyes for this recipe. Not only will I be printing this one, I will be doubling it and serving it at every opportunity. It is easy and incredible exactly how the instructions say- no modifications needed.
I’m thrilled you and your husband enjoyed the casserole. Thank you so much for the feedback.
This recipe is fantastic. Great if you use GF bread crumbs too. I added ground chicken and onion and it was really very good. This would be a great way to get your kids to eat their vegetables.
Great idea to add ground chicken, Julie! We’re so glad you enjoyed it! Thanks for sharing!
This is delicious! I added a chopped onion and 2 tbls basil because we love it. I used garlic infused oil instead of garlic powder and added a tsp of onion powder. After cooking in a pan I spread out on a cookie sheet instead of using a 9×13 so it wouldn’t be soggy. I topped with extra Parmesan. I baked until very brown and squeezed juice of a lemon over all. It’s a keeper.
Great tips! Thanks for the feedback, Linda.
I feel like it would be better with a measured amount of zucchini & squash instead of saying “2 small”. That is extremely subjective. I started with 1 decent sized zucchini and a decent sized squash thinking those probably were the same as 2 small but it wasn’t nearly enough. So what I ended up using seemed to be 2 medium zucchini. But again, it’s all subjective.
That being said, this was DELICIOUS! Next time we are gonna add some stuff to make it a main dish instead of a side dish. Great recipe!
Delicious. But I add a thin layer of shredded block mozzarella cheese. Probably changed everything. But I wouldn’t have altered at all. It would have been delicious I know. I will want to serve this exact recipe always if it consists of zucchini and/or spinach.
Love this recipe! It’s a regular in our house. I served it to company and got requests to share the recipe! So easy to make, so delicious!
We love to hear that, Rose!
Can you freeze this after it is cooked?
Caroline, Yes, but make sure it cools down before freezing. And, allow to thaw in the fridge before cooking or reheating.
I am so excited to try this! We have just started a vegetarian diet and after reading some reviews, I plan to double the recipe because we will have this as a main course. I was wondering if you think adding a bit of quinoa for some more healthy protein would be a good idea? Thank you so much for sharing your recipe!
Christina, I think adding some quinoa would be a delicious addition. 🙂
This is a winner! If anyone is wondering a flax egg works as well. 1T flax to 2T water. Added onion and garlic with the saute as many suggested. Used 8×8 casserole dish. Thank you!
Awesome, Melody!Thanks for the great tips! We’re glad you enjoyed it ?
LOVED this recipe!! I made quite a bit of modifications and it turned out wonderfully. I added minced garlic and onion, sliced mushrooms, and a pound of ground turkey sausage (cooked on it’s own beforehand and added to the spinach mixture before adding it all to the breadcrumbs) and only used 1 whole egg. I’ll be doubling the recipe next time ????
Fantastic, Stacy! Your additions sound AMAZING! We’re so happy you loved it! Thank you for the great feedback! ????
I have a carton of liquid egg whites on hand. How much would I use for the recipe?
Monica, This recipes doesn’t call for egg whites. If you prefer to use them, add about 1/2 cup to the mixture before baking.
Could you use Kale instead of Spinach? Would it wilt as well as Spinach
Looking forward to trying this recipe:)