These portobello mushroom fajitas are one of my favorite recipes! This veggie fajitas recipe with homemade fajita seasoning is family friendly and vegetarian. Portobello fajitas are filling and their texture is thick and satisfying–like chicken. Mushroom fajitas are a perfect Meatless Monday recipe!

Nutrition Information
I love learning about food as I cook it! Here’s what I’ve learned about the vegetables that are in this fajita recipe:
Mushrooms are a nutrient dense vegetable–you can learn more about portobello mushrooms here, but here are the main points:
- high in antioxidants and anti-inflammatory properties
- high in Vitamin D
- contain selenium (which supports the immune system)
- high in fiber
I like that portobello mushrooms have a thick and hearty texture–very similar to chicken. When I’m looking to make a delicious vegetarian meal, portobello mushrooms are one of my main go-to vegetables.
Bell Peppers are considered a nightshade vegetable, and can be eaten raw or cooked. They’re super high in vitamin C and other antioxidants. Green belle peppers are actually just unripe red, yellow, and orange peppers! They haven’t matured to their sweet and ripe state yet.
Zucchini is a type of squash. It contains calcium, iron, and antioxidants–this fajita recipe contains a lot of antioxidants!
Onions contain a high amount of Vitamin C and B. They also contain a lot of potassium, which can help stop muscle cramps. And again with the antioxidants!
Like I mentioned above, the vegetables in this recipe contain a lot of antioxidants. But…what the heck are antioxidants?
Here’s the short story about them. Click below to learn more.
Antioxidants are tiny molecules that help fight free radicals in your body. Free radicals are things that normally don’t cause issues but when there are too many of them, they can cause disease. Antioxidants keep the free radicals in check.
My family loves this recipe, it’s one of my favorites that I make when we’re craving Mexican food. Leave a comment below and tell me what your family and friends think of this delicious recipe!
Ingredients in Portobello Mushroom Fajitas:
- portobello mushrooms
- bell peppers (any kind)
- zucchini
- onion
- veggie fajita seasoning (for the mushrooms–make sure to use the smoked paprika!)
- vegetable seasoning (for the other vegetables–see below for the recipe)
- corn tortillas, or flour tortillas–whichever you prefer.
- spray oil (I use olive oil or avocado oil)

Homemade Vegetable Seasoning:
- 2 tbsp black pepper
- 1 tbsp salt
- 1 tbsp garlic powder
- 1 tbsp onion powder
- 1 tsp coriander
- 2 tsp dry mustard
- 2 tsp dill
- 2 tsp rosemary
- 1 tsp red pepper
Adding in a little chipotle powder will give this recipe a slightly smoked taste–try it!

When slicing vegetables, make sure they’re all the same thickness. This will ensure they’re done cooking at the same time. If you prefer certain veggies less cooked and more crisp, slice those thicker.
How to make Portobello Fajitas:
- Slice portobello mushrooms and spray slices with oil. Sprinkle fajita seasoning on them.
- Slice zucchini, peppers, and onions.
- Place a small drizzle of oil (maybe 1 tablespoon?) and about 1T of veggie seasoning in with veggies. Toss them together.
- Grill at 350º for 15-20 minutes or until cooked to your liking. I prefer mine a bit undercooked, so they’re crunchy!
- Serve with corn or flour tortillas, on top of zoodles, or on a salad! Watch the video for my tips about making warm tortillas!
Stovetop Instructions:
If cooking these fajitas on the stovetop, I’d cook over medium-high heat for 10-15 minutes or until vegetables are cooked to your liking.
How to serve Portobello Mushroom Fajitas:
Serve these fajitas with corn or flour tortillas, on top of a salad, with zucchini noodles, or even add some black beans for extra protein and serve as a “bowl.” If I wanted to add more veggies to it, I’d heat up some cauliflower and serve these fajitas on a bed of warm cauliflower.
Add greek yogurt, sour cream, cottage cheese, cilantro, salsa, or squeezed lime juice as garnish.
Looking for more healthy recipes that are vegetarian?
- Easy Breakfast Tacos
- Cauliflower Steaks with Chimichurri
- Baked Blooming Onion
- Buffalo Cauliflower Bites
How about more Mexican Food Recipes?
- Carne Asada (plus a ton of delicious recipes for leftovers!)
- Southwest Egg Roll in a Bowl
- Chorizo and Eggs
Products used in this recipe:
Le Creuset Braiser (I love using the top to hold corn tortillas and the bottom to hold the meal–it looks great on the table!)

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Special Diet Information:
21 Day Fix: One serving of this recipe is two green containers and one yellow container. You could also just fill your green container up with veggies if you’d like!
WW Blue, Green and Purple Plans: The veggies are zero points. If you’d like to add corn tortillas, add three points for 2 tortillas.
2022/2023 Plan: Each serving is 2 points
2B Mindset: Without the tortilla, this is a perfect 75% dinner recipe, just add some edamame or other protein as a side dish. With tortillas, this is a great lunch recipe for 2B, just add 25% protein (edamame, tofu, tempeh) and you’re set!
Portobello Mushroom Fajitas
Ingredients
- 2 portobello mushrooms thick slices
- 1 cup zucchini sliced
- 1 cup green bell pepper sliced
- 1 cup red bell pepper sliced
- 1 cup onion sliced
- 1 cup orange bell pepper sliced
- 1 cup yellow bell pepper sliced
- 8 corn tortillas or flour
Instructions
- Slice portobello mushrooms into thick slices and spray with oil.
- Sprinkle homemade fajita seasoning on them
- Slice the onions, zucchini, and peppers. Add about 1 tbsp of oil and toss with about 1 tbsp of vegetable seasoning.
- Grill at 350º or cook on stovetop for about 15 minutes, or until vegetables are cooked to your liking.
- Serve with corn or flour tortillas, on top of zoodles, or on a salad.
Asparagus baked in the oven is also a good addition to this recipe.
This is so delicious 😋, I had all ingredients and made it for lunch! Another winner! Thank you sooo much. The Best!
These are delicious! Even my husband who wants some kind of meat with a meal really liked these. Loved the video to show us how you cooked them. Made the fajita seasoning and veggie seasonings. Another great recipe to add to a dinner rotation.
I don’t have a grill. Stove at 350.?..
Perfect! Maybe 20 minutes or so :)