Grilled Cheese With Caramelized Onions

4.50 from 2 votes

Gooey cheddar cheese and slow-cooked onions join in a harmonious pairing between two slices of whole-wheat artisan bread.

Our Grilled Cheese with Caramelized Onions is full of delicious and satisfying flavor.

Our grilled cheese with caramelized onions is the grown-up, sophisticated grilled cheese revamp you’ve been looking for. Between two slices of whole-wheat artisan bread, cheddar cheese and slow-cooked onions join in a most harmonious pairing. Like peanut-butter and jelly, but infinitely better. We looked into every which way to save on the fat count. Because of that, this sandwich has been artfully constructed for the optimal comfort food experience– minus the guilt. And, because we know you don’t like fake food either, we kept the ingredients all natural! 

Fitting this Grilled Cheese Into Your Diet 

This ooey gooey grilled cheese is a quick and easy comfort food!

When it comes to the calories found in bread, all of them are pretty much the same. That said, whole wheat and whole grain bread offer complex carbohydrates, while white bread offers simple carbs. Sourdough can be either/or depending on the flour that was used to make it (whole wheat or all purpose). What’s the difference between complex and simple carbs?

Complex carbhoydrates are less processed and slower digesting, so they’re an excellent choice in the morning because they can provide you with longer lasting energy. If you’re going to be working out in a few hours, whole wheat or whole grain bread is a good option. Simple carbohydrates on the other hand, provide the fastest energy. So, if your workout is coming up within the next 30 minutes to an hour, white bread or sourdough is the way to go. But, as far as weight loss is concerned, the timing of your carbs doesn’t matter as much as your total intake throughout the day. If you’re eating an appropriate balance of protein, carbs, fat, and calories for your body, you’ll be just fine.

If you feel the need to off-set this “cheat meal” you can do so by making healthier choices later in the day. Grab some fruit, drink a protein shake, or make a big salad for dinner with a lean protein like chicken or shrimp. Planned wisely, you can fit this grilled cheese sandwich into your day without stressing about your diet!

Grilled Cheese With Caramelized Onions Needs Patience

Treat yourself to a creamy and savory grilled cheese sandwich without any guilt!

Caramelized onions are very time consuming, and for that matter, extremely challenging to make when you want them now. For that reason alone, schedule the cooking when you are already planning on spending some time in the kitchen.

I’ve tried nearly all methods of caramelizing onions. The most important part of getting it right is to keep the heat low for a long time. If the burner’s too hot, you risk cooking the exterior too soon. At that point, the onions have a char quality that doesn’t work flavor-wise. Now, although some people recommend starting with a hot pan, that’s not a good idea, either. Getting the temperature to regulate can be detrimental if you can’t gauge how soon the pan can cool down.

Using a large enough pan that has higher walls than a typical skillet is also extremely helpful. Due to all the water that’s naturally occurring in the onions, you need to be able to keep some moisture in order to maintain a slow roll. Shallow walls will inevitably lead to a dryer surface, which could prematurely dry out the onions. Subsequently, they’d burn a lot faster. 

Sophisticated Grilled Cheese On Low Heat

Satisfy your cravings for cheesy comfor with this yummy grilled cheese!

In order to get that great golden crust on the bread, we chose mayonnaise as the fat. Believe it or not, mayo typically has less fat and calories than butter. It also can withstand high heat better, so if you are in a hurry, this is your hack. If not, then butter or oil also gets the job done. 

A little sweetness in the form of jam, preserves, apple or pear slices is tasty. I chose raspberry jam for my most recent tasting of this grilled cheese sandwich, and it was the jam! Serve this sophisticated grilled cheese sandwich for everyone and anyone! A cup of tomato soup would make it mighty fine.

4.50 from 2 votes

Grilled Cheese With Caramelized Onions

A sophisticated remake of a timeless classic
Prep Time 10 minutes
Cook Time 1 hour 15 minutes
Total Time 1 hour 25 minutes
Yield 2 People
Serving Size 1 sandwich
Course Dinner, Lunch
Cuisine American


Caramelized Onions

  • 2 yellow onions medium sized
  • 2 tablespoons butter unsalted
  • 1 pinch of salt
  • 1/8 cup water
  • 2 tablespoons balsamic vinegar

Grilled Cheese

  • 4 whole wheat bread slices Sourdough or whole-grain very good too
  • 2 tablespoon mayonnaise 1 1/2 teaspoon on each slice (4)
  • 1 cup reduced fat cheddar cheese


Caramelized onions

  • Peel and halve the onions, with the root part facing up. Cut a V-shaped notch around the root on both halves to fully remove the part that interferes with slicing. When you do slice the onion, all slices will individually separate.
  • With the root part facing up, slice one half lengthwise, moving from one end to the other. Optimal width of each slice should be between 1/8-1/4 inch. Repeat with other 3 halves.
  • In a large, wide pan with high sides, melt 2 tablespoons of butter over medium heat. Once the butter is sizzling, add half of the onions. Cook for 2-3 minutes, until they are translucent. Then add the other onions and a pinch of salt.
  • Reduce heat to medium low, keeping an eye on the onions, stirring every five minutes. After 15-20 minutes, the onions should start looking light tan/blonde. If, at that point, the pan begins to look dry, add 1/8 cup water or chicken broth. Do not stir anymore, unless you see the edges crisping up. If that happens, reduce the heat.
  • The time it takes for the onions to reach a deep brown can be anywhere between another 15 minutes to 45 minutes. If at the 20 minute mark, they haven’t gotten brown enough, then turn the heat up and watch them closely. At this point you need to stand by until they look nice and brown.
  • Add balsamic vinegar to the onions and de-glaze the pan to get all the good bits off. The vinegar will enhance the sweetness a great deal and make it jammy.

Grilled Cheese Sandwich

  • Warm a cast iron griddle pan (something that can accommodate 4 pieces of bread) to medium heat for five minutes.
  • Spread 1 1/2 teaspoons on one side of four slices of bread. Place on pre-heated pan and add 1/2 cup cheese to two slices.
  • Warm up 2/3 cup of caramelized onions on free space on griddle or in the microwave for 45 seconds. Once cheese has melted, then add the onion to the cheese side. Top the sandwiches with remaining slices. Serve.


To reduce calories and carbs, you can make this open-faced on one piece of bread. Jam, jelly, or preserves of any kind really up the flavor ante here. Also, pear or apple work wonderfully if you want something sweet without refined sugar. 
Cheddar is highest in calories. For a flavor parade and more sophistication, try Parmesan, Brie, and mozzarella mixed together.

Nutrition Information

Serving: 1sandwich | Calories: 378kcal | Carbohydrates: 38g | Protein: 22g | Fat: 15g | Saturated Fat: 7g | Trans Fat: 1g | Cholesterol: 29mg | Sodium: 752mg | Potassium: 361mg | Fiber: 6g | Sugar: 11g | Vitamin A: 306IU | Vitamin C: 8mg | Calcium: 327mg | Iron: 2mg |
SmartPoints (Freestyle): 13
Keywords Kid-Friendly

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Try this Creamy Tomato Soup for the perfect pairing! These Sautéed Brussels Sprouts with Garlic will balance the meal perfectly.

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Alison Borel

Alison Borel came into the culinary world by owning and operating three family restaurants with her husband in San Diego. During that time, she tested, wrote, and taught all the recipes used by her team. She also led cooking classes for small groups. Familiar with vegan and vegetarian cuisine from working in an organic cafe and camp, her preference lies in a plant-based whole foods diet. Alison knows eating for longevity and nutrition not only tastes good, but feels good too.

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