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Roasted Portobello Mushroom Fajitas

Easy and healthful vegetarian fajitas with roasted portobello mushrooms, bell pepper, onion, and spicy chipotle sour cream.

Roasted Portobello Mushroom Fajitas with Chipotle Sour Cream | #healthy #vegetarian #meatlessmonday #glutenfree #dinner

I’m back in the lower 48 after my 10-day trip to Alaska! It was so hard to leave that incredible state, but I have every intention of a return visit. From Copper River Salmon teaching me so much about sustainable fishing and the local environment, to poking around Homer and Seward, and even hiking to a ginormous glacier, Alaska was an absolutely marvelous adventure. Hang tight, I’ll share with you a barrage of information as soon as I nestle back in and have a chance to edit all my photos.

In the interim…



Simplest weeknight meal, and perfect for Meatless Monday.

The fajita style of cooking – multi-color bell peppers and onion combination, spiced to perfection – is a definite YES to my palate. From Crock Pot Shredded Chicken Fajita Chili to a more classic approach like these little tacos, I could fajita every which way on the reg. Chicken fajitas made it on the table at least once a month when I was a kid. My mom was all about whipping up big batches to satisfy me and my siblings, as anything that required a tortilla and cheese was always a-okay by us.

Case in point: Fajitas are easy to make in bulk, or to scale down depending on how many people you’re serving. Plus, they’re ultra bangarang with you whip up a batch of chipotle sour cream and homemade guacamole for tying everything together in creamy bliss.

Roasted Portobello Mushroom Fajitas with Chipotle Sour Cream | #healthy #vegetarian #meatlessmonday #glutenfree #dinner

If you didn’t get your fill of portobello mushrooms from those Grilled Portobello and Summer Squash Quesadillas I showed you a couple of weeks ago, here’s your chance to get your fix!

Rather than making this particular batch of fajitas with chicken, shrimp, or beef, I skipped the animal protein and used portobello mushrooms to make the meal “meaty.” If you’re amped for some animal, feel free to use your favorite protein for a well-balanced fajita adventure.

This is how you rock down to Fajita Avenue:

Roasted Portobello Mushroom Fajitas with Chipotle Sour Cream | #healthy #vegetarian #meatlessmonday #glutenfree #dinner
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5 from 1 vote

Roasted Portobello Fajitas

Roasted Portobello Fajitas are hearty plant-based fajitas!
Prep Time5 minutes
Cook Time25 minutes
Total Time30 minutes
Course: Main Dishes, Meatless Main Dishes
Cuisine: American
Servings: 6 Servings
Calories: 380kcal
Author: Julia


  • 2 large portobello mushrooms
  • 1 red bell pepper cored and chopped
  • 1 orange bell pepper cored and chopped
  • 1 pasilla pepper cored and chopped
  • 1 red onion diced
  • 2 cloves garlic
  • 3 tablespoons to 4 olive oil
  • 2 teaspoons chili powder
  • ½ teaspoon ground cumin
  • ½ teaspoon paprika
  • ¾ teaspoon sea salt to taste
  • Corn tortillas for serving

Chipotle Sour Cream:

  • 2/3 cup sour cream
  • 3 in chipotle chilis adobo sauce or more for a spicier sauce
  • 2 tablespoons fresh lime juice
  • 1 teaspoon pure maple syrup optional
  • Pinch sea salt

Easy Guacamole (optional):

  • 2 large avocados pitted and diced
  • 3 tablespoons lime juice
  • 2 cloves large garlic minced
  • 1 small jalapeno seeded and chopped
  • sea salt


Roast the Vegetables:

  • Preheat the oven to 415 degrees F. Line one large baking sheet with parchment paper, and lightly oil one small casserole dish.
  • Coat the full surface of the portobello mushrooms with olive oil and sprinkle both sides with salt. Place them gill-side up in the prepared casserole dish.
  • Spread the bell peppers, pasilla pepper, and onions over one baking sheet and drizzle with enough olive oil to coat the vegetables, about 2 to 3 tablespoons. Sprinkle with chili powder, cumin, paprika, and sea salt. Use your hands to toss the peppers and onion until everything is well coated in oil and seasonings.
  • Place both the sheet of peppers and the casserole dish with the mushrooms into the preheated oven. Roast for 20 to 30 minutes, flipping the mushrooms and stirring the peppers half-way through, or until peppers and mushrooms are golden-brown, and cooked through.
  • Remove from the oven and allow vegetables to cool slightly. When cool enough to handle, transfer the portobello mushrooms to a cutting board and cut into thick slices.

Prepare the Chipotle Sour Cream:

  • While the vegetables are roasting, prepare the chipotle sour cream sauce and the guacamole.
  • Add all of the ingredients for the chipotle sour cream to a bowl and stir well until combined. Taste sauce for flavor and add more lime juice, sea salt, adobo chilies, and/or adobo sauce to taste. Cover and refrigerate until ready to use.

Prepare the Guacamole:

  • Add the ingredients for the guacamole to a bowl and mash and stir until guacamole reaches desired consistency. If desired, add more goodies, such as red onion, chopped tomato, cilantro, salsa, etc. Cover and refrigerate until ready to use.

Prepare the Fajitas:

  • Toast corn tortilla ovens on the stovetop or in the oven until crispy. Load them up with desired amount of roasted portobello, bell peppers, chipotle sour cream, and guacamole. Garnish with fresh cilantro if desired.


Serving: 1fajita | Calories: 380kcal | Carbohydrates: 54g | Protein: 20g | Fat: 10g | Fiber: 3g
Recipe Rating

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Shelley Ottenbrite

Tuesday 2nd of October 2018

I have a question about the pasilla pepper -- which is a dried chilaca pepper. Could you possibly mean a fresh poblano pepper instead? Thank you for your help -- I don't know how to use pasilla peppers.


Wednesday 3rd of October 2018

Hi Shelley, the pasilla pepper is fresh (not dried) as well, but you can definitely use a poblano pepper! Hope you enjoy!


Saturday 3rd of March 2018

Wonderful. I have been searching for some ingredient to change up fajitas, and when I saw portobello mushrooms, I figured I had found it. Thanks! I have a special griddle for fajitas, so we will try adding portobellos to the mixture and see what happens. I love portobello burgers, so I have high hopes. I hope you keep innovating - what's life for if it's not new ideas?

Kari Peters

Thursday 15th of September 2016

Your Alaska trip looked amazing, I can't wait to see the recap! Who needs meat when your fajitas look like this, and that chipotle sour cream... what!?!

Medha @ Whisk & Shout

Tuesday 13th of September 2016

These fajitas look insane! Love the chipotle sour cream and all those veggies, especially the savory portobellos :)


Wednesday 14th of September 2016

They're pretty dern tasty! Glad you like them, Medha!

Sarah @ Making Thyme for Health

Monday 12th of September 2016

I can't wait to see and hear all about your Alaska trip! I was just telling B how sad I am that we didn't get to go there while we were on the west coast. It looks unreal.

And I'm always down for a good mushroom fajita. I love the sound of that chipotle sour cream. Holy yum!!

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