Plant-Based Portobello Fajita Skillet

4.67 from 3 votes

The perfect rendition of a vegan fajita.

Our plant-based portobello fajita skillet is meaty in texture but 100% vegan-friendly!

This plant-based portobello fajita skillet is a riff on the popular Tex-Mex dish, and it’s a winner for your next Meatless Monday’s dinner! We treated the beefy portobello as meat, marinating them as we would a skirt steak. Then we sizzled up multi-colored bell peppers and onions in fajita seasoning before pulling it all together in the same skillet. Just like that: A perfect rendition of a vegan fajita.

This one’s guaranteed to convert the most reluctant mushroom hater into a mushroom acceptor. And if your tribe already subscribes to mushroom loving, they’ll dig this all the more.

Treating Mushrooms Like Meat Make Them Meaty

This super simple recipe makes a great swap for a healthier taco Tuesday!

There are loads of tricks to make mushrooms taste like meat. My personal favorite is to marinate them in the exact same recipe you’d use for steak. In the case of fajitas, skirt steak needs marinade due to the toughness of the cut. Fajitas were created by a group of ranchhands on the border given tough cuts of meat to eat as chow. To make them tasty, they marinated their meat in lime, molasses, vinegar, and spices before grilling up the magic. This portobello fajita skillet uses the traditional marinade, except we shift with tamari and date syrup to make some healthful updates.

When you cut your portobellos, cut them exactly as you would steak strips, but a little thicker. They do cook down, so you don’t want them to be itty bitty slivers. The point is to give them a meaty appearance. We don’t want the seasoned veggies to overpower the awesome flavor of the mushrooms!

Sizzle Veggies On High Heat, Then Simmer

Our delicious vegan fajita skillet makes an excellent dinner and leftover lunch.

Bell peppers are prettier when you use a combination of colors: red, yellow, and orange. If you don’t have all the colors, don’t worry; the taste remains no matter if you only have one color to choose from. To get your peppers and onion a good char, start with a high heat and leave them alone for a few minutes. They’ll develop that nice crispy look we love when served on a sizzling hot plate in Mexican restaurants.

After the veggies acquire that good char, turn down the heat to ensure the insides of the veggies soften. If you like your veggies more crunchy, don’t cook them for much longer. A grill or grill pan also work well with portobello fajita skillets. They leave those beautiful grill marks we all love.

Serve As You Would Traditional Fajitas

This flavorful dinner is so good that you'll never miss the meat!

Fajita lovers expect a side of tortillas to make their own tacos at the table. With a lime wedge and possibly a bit of avocado, salsa, or crema, you’ll nail the vegan fajita with flair. Traditionally paired with a side of beans and rice, fajitas really are a complete meal. What we love about them is the emphasis on vegetables that steer you clear of any unwanted fats or hollow calories. 

It’s no wonder everyone in the restaurant turns to regard a sizzling cast iron plate. Now you can have your turn at home. If you love this dish, you might want to take it up a notch at home with your own sizzling fajita plate. However, this dish presents very well in a regular cast iron pan in the middle of the dinner table. Fajitas were born for family style sharing.

4.67 from 3 votes

Plant-Based Portobello Fajita Skillet

This simple, plant-based fajita skillet is the perfect topping for Mexican tacos, bowls, or salads!
Prep Time 5 minutes
Cook Time 15 minutes
Marinate 30 minutes
Total Time 50 minutes
Yield 4 people
Serving Size 0.5 cup
Course Dinner, Lunch
Cuisine Mexican


  • 4 portobello mushrooms large, sliced
  • 2 yellow onions large, sliced
  • 2 bell peppers any color, large, sliced
  • 2 tablespoons olive oil
  • 1 tablespoon lime juice
  • 1/2 teaspoon ground cumin
  • 1/4 teaspoon smoked paprika
  • 1 teaspoon oregano
  • 1 pinch ground cayenne pepper
  • 1/2 teaspoon salt
  • 1 teaspoon pepper

Portobello Marinade

  • 3 limes juiced, (2 tablespoons)
  • 2 tablespoons red wine vinegar
  • 2 teaspoons tamari or soy sauce
  • 2 teaspoons date syrup or sweetener of choice
  • 2 teaspoons cilantro
  • 1 garlic cloves
  • 1/4 teaspoon cumin
  • 1/4 teaspoon black pepper


Marinate Mushroms

  • Combine marinade in a liquid measuring cup. Place mushrooms in a zip-locked bag or plastic container, add the marinade and shake until mushrooms are evenly coated. Marinate for at least 30 minutes.

Bell Peppers and Onions

  • Toss veggies with olive oil, lime juice, and seasoning.
  • Cook veggies in a large skillet, medium high heat, until soft. 15-20 minutes.

Cook Mushrooms

  • At the same time, saute mushrooms in a medium sized skillet, medium high heat, until soft. 10-15 minutes.
  • Combine mushrooms with other vegetables, taste for doneness and add more seasoning, if desired.


  • Serve as taco filling with beans and rice or in a bowl.

Nutrition Information

Serving: 0.5cup | Calories: 146kcal | Carbohydrates: 19g | Protein: 4g | Fat: 8g | Saturated Fat: 1g | Trans Fat: 1g | Sodium: 473mg | Potassium: 605mg | Fiber: 5g | Sugar: 8g | Vitamin A: 1983IU | Vitamin C: 96mg | Calcium: 54mg | Iron: 2mg |
SmartPoints (Freestyle): 6
Keywords Plant-Based

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Try pairing your fajitas with cashew queso in this Plant-Based Bell Pepper Nacho Boats with Avocado Sauce and Cashew Queso. And these Refried Beans are also a mindful Tex-Mex match.

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Kelsey Butler, MS, RDN

Kelsey Butler is a Registered Dietitian and recipe developer. From a young age, Kelsey found a love for creating delicious recipes. Now, with a Master's in Nutritional Sciences, Kelsey uses her culinary skills to create healthy and unique recipes for many different diets. She is passionate about creating a healthy relationship with all foods and recipes that everyone can enjoy. Kelsey has a passion for cooking, but she also enjoys the outdoors, staying active, and traveling. She is currently living with her partner in New Zealand.

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