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Mushroom Fajitas

by Katerina

5 from 16 votes

Mar 03, 2022, Updated Jul 25, 2024

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This portobello mushroom fajita recipe is hearty and meatless, bursting with spicy Tex-Mex flavor! With colorful peppers, savory onions, and meaty slices of portobello mushrooms, these vegetarian fajitas are a nutritious and mouthwatering meal that’s sure to please.

Vegetarian Fajitas Recipe

Fajitas are truly awesome. They just are, and that’s a fact. No one should resist the combination of sizzling peppers and onions, cooked to crisp-tender perfection with your favorite protein. And, while I’m definitely a fan of beef fajitas, chicken, and even shrimp fajitas, sometimes you need a good meatless entree. Enter easy portobello mushroom fajitas!

In this vegetarian fajita recipe, slices of portobello mushrooms take the place of meat, but trust me, even dedicated carnivores won’t miss it! Portobellos are known for their “meaty” texture and flavor, and when they’re sliced thinly, they’re just right for fajitas.

Also, the cooking method couldn’t be more simple: just season your veggie blend, arrange it on a sheet pan, and bake until tender. It’s a super-easy, uber-flavorful dinner that’s just perfect for busy families!

What You’ll Need

So, what ingredients will you need to make these quick, vegan, and vegetarian fajitas? I’m glad you asked! Here’s a quick rundown of each ingredient and some tips for easy substitutions.

• Olive Oil: This is my go-to, but you could substitute avocado oil, or any other cooking oil that you prefer.
• Lime Juice: A little acidity is so important in fajitas—it brings out the flavors in the seasoning mixture and in the vegetables. If you don’t have lime juice, use lemon juice, or you could substitute your favorite vinegar. (Keep in mind that some vinegars have a stronger fragrance and flavor than lemon or lime juice).
• Homemade Fajitas Seasoning: You can use store-bought fajita seasoning, or make a quick batch of my amazing homemade fajitas seasoning!
• Cayenne Pepper: Use this to taste, to add a spicy kick. If you don’t care for the heat of cayenne pepper, you can leave it out.
• Portobello Mushrooms: You’ll want to get a few large portobello mushrooms, and slice them into ½-inch strips.
• Bell Pepper: I like to use one each of red, green, and yellow bell peppers, but using just one color is totally fine. Slice the bell peppers thinly.
• Yellow Onion: Red, white, or sweet onions are also fine. Slice thinly, just like the bell peppers.
• Flour Tortillas: For serving. 
• Optional Toppings: You can top the fajitas simply with a dollop of sour cream or go all out with avocado tomatillo salsa, avocado slices, chopped fresh cilantro, lime wedges, and any other toppings or garnishes that you like. 

How To Make Mushroom Fajitas

These delicious vegetarian fajitas require little prep and take very little time to put on the table. Slice your veggies, combine them with the seasoning mixture, and bake to perfection.

1. Get Ready. Once your ingredients are assembled and ready to go, preheat your oven to 450˚F. Then, line a large baking sheet with foil. Set the baking sheet aside.
2. Season Your Veggies. Get a large mixing bowl, and combine the olive oil, lime juice, fajitas seasoning, and cayenne pepper in it, giving it a good stir to mix. Add in your mushroom slices, peppers, and onions, and gently toss them to coat in the oil. Then transfer the veggies and mushrooms to your prepared baking sheet, and spread them out in a single layer.
3. Bake, and Serve. Bake for about 15 minutes, or until the vegetables are tender. Take them out of the oven, and serve with flour tortillas and toppings of choice.

Serving Suggestions

If you’d like to add a side dish or two to the menu, some of my favorites to go with a plate of vegetarian fajitas include these vegetarian meatballs with a Southwestern orzo salad packed with corn, black beans, and creamy avocado.

Cornbread is good with just about anything, but I think it goes particularly well with Tex-Mex flavors. This light skillet cornbread is baked the old-fashioned way in a cast-iron skillet. Pair it with the fajitas and a bowl of my Minestrone soup for a full meal.

Parmesan potatoes with fajitas is one amazing combo! My kids love it! Also, try these lemon garlic roasted potatoes for a grain-free side that’s still hearty and filling.

How to Store and Reheat Leftovers

To store, place your leftovers in airtight containers or food storage bags, and refrigerate. Properly stored, they’ll keep for 3 to 4 days or freeze for 1 month. Note that the frozen vegetables are likely to become soft and mushy once they’re thawed and reheated.

To reheat, place the desired portion in a covered skillet, over low heat. Heat until the veggies are sizzling and heated through, but don’t overcook, or they’ll become soft and mushy. You can also bake leftover portobello fajitas at 450˚F until hot. 

More Tex-Mex Recipes

• Quick Pork Carnitas Tacos
• Tex Mex Cheesy Beef Quiche
• Tex Mex Chicken Salad
• Instant Pot Chicken Tinga
• Mexican Street Corn Salad with Grilled Chicken

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5 from 16 votes

Mushroom Fajitas

by Katerina | Diethood

With colorful peppers, savory onions, and meaty slices of portobello mushrooms, these vegetarian mushroom fajitas are a nutritious and mouthwatering meal that’s sure to please!

Prep Time: 10 minutes minutes

Cook Time: 20 minutes minutes

Total Time: 30 minutes minutes

Servings: 4

Ingredients 

1x2x3x

• ▢ 3 tablespoons olive oil
• ▢ 3 tablespoons fresh lime juice
• ▢ 2 tablespoons homemade fajitas seasoning
• ▢ ¼ teaspoon cayenne pepper
• ▢ 3 to 4 large portobello mushrooms, cut into ½-inch thick slices
• ▢ 1 red bell pepper, sliced into strips
• ▢ 1 green bell pepper, sliced into strips
• ▢ 1 yellow bell pepper, sliced into strips
• ▢ 1 yellow onion, thinly sliced
• ▢ 8 low carb flour tortillas, for serving
• ▢ lime wedges, for serving
• ▢ salsa, for serving, optional
• ▢ avocado slices, for serving, optional
• ▢ chopped fresh cilantro, for serving, optional
• ▢ sour cream, for serving, optional

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Instructions 

• Preheat the oven to 450˚F.
• Line a large baking sheet with foil and set aside.
• In a large mixing bowl combine olive oil, lime juice, fajitas seasoning, and cayenne pepper; mix until incorporated.
• To the bowl add the mushroom slices, peppers, and onions; toss to combine.
• Transfer the peppers and mushrooms to previously prepared baking sheet and arrange in one single layer.
• Bake for 15 to 18 minutes, or until veggies are tender.
• Remove from oven.
• Serve with flour tortillas and optional fillings and toppings.

Nutrition

Serving: 2fajitas | Calories: 152kcal | Carbohydrates: 13g | Protein: 3g | Fat: 11g | Saturated Fat: 2g | Polyunsaturated Fat: 1g | Monounsaturated Fat: 8g | Trans Fat: 1g | Sodium: 124mg | Potassium: 463mg | Fiber: 4g | Sugar: 5g | Vitamin A: 1276IU | Vitamin C: 123mg | Calcium: 21mg | Iron: 1mg

Nutritional info is an estimate and provided as courtesy. Values may vary according to the ingredients and tools used. Please use your preferred nutritional calculator for more detailed info.

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