I got that craving for fajitas the other day and just had to have ’em. I decided to switch things up a bit from my usual sheet pan fajitas and use portobello caps in place of the chicken. I also added a little smoky chipotle powder to the spice mix to keep things interesting. These Sheet Pan Portobello Fajitas are a new and welcome twist on the classic. A little squeeze of lime on top and a slice or two of creamy avocado, and you have a really tasty veggie-filled dinner.
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Portobello Mushrooms on a Budget
Portobello mushrooms aren’t the cheapest item in the produce aisle, so it’s important to use some of our budget byting principles here. First, make sure you compare prices both between available grocery stores and even within the store. If your grocery store sells them both packaged together and loose, be careful to compare the per-pound price because it might be cheaper to buy them loose!
Second, we’re going to combine the portobello mushrooms with other ingredients that are much less expensive, like onions, bell peppers, and tortillas to balance out the total price and keep the price per serving on the low side.
Make it Spicy or Mild
The recipe, as written below, is a little smoky and spicy thanks to the chipotle powder in the fajita spice mix. If you prefer a mild fajita, skip the chipotle powder and make sure to use a chili powder blend that is mild. If you want your fajitas to be smoky but not spicy, replace the chipotle powder with smoked paprika.
Meal Prep It!
The filling for the fajitas works great as a meal prep. Just pack up the roasted mushroom, pepper, and onion mix in a lunch container with a slice of lime and a couple of tortillas. When it’s time for lunch, remove the tortillas and lime, reheat, then fill the tortillas, squeeze your lime, and enjoy!
For the avocado, I suggest slicing a few slices off the whole avocado each day. Only the exposed surface will darken, and it only darkens slightly (it doesn’t turn completely black like mashed avocado). The darkening of the avocado does not mean it is spoiled, it just means that it has been exposed to oxygen (like a brown apple), and is still perfectly safe to eat.
What to Serve with Portobello Fajitas
Sweet Corn Salsa or Summer Sweet Corn Salad would be a wonderfully light and fresh contrast to these portobello fajitas. And if you want to dress them up a little bit more you could whip up a quick batch of Guacamole or Pico de Gallo!
Sheet Pan Portobello Fajitas
Ingredients
FAJITA SPICE MIX
- 1 Tbsp chili powder* ($0.30)
- 1/2 tsp chipotle powder ($0.05)
- 1/2 tsp onion powder ($0.05)
- 1 tsp cumin ($0.10)
- 1/2 tsp garlic powder ($0.05)
- 1 tsp sugar** ($0.05)
- 1/2 tsp salt ($0.03)
FAJITAS
- 2 portobello mushroom caps ($3.99)
- 2 bell peppers (any color) ($2.29)
- 2 yellow onions ($0.64)
- 3 Tbsp olive oil ($0.38)
- 8 small flour tortillas (6-inch) ($1.00)
- 1 avocado ($1.09)
- handful cilantro (optional) ($0.25)
- 1 fresh lime ($0.59)
Instructions
- Preheat the oven to 400ºF. In a small bowl, stir together all the ingredients for the fajita spice mix
- Slice the portobellos, bell peppers, and onions into 1/4 inch wide strips. Place the sliced vegetables on a large sheet pan. Drizzle the olive oil over the vegetables then sprinkle the fajita spice mix over top. Use your hands to toss the vegetables until everything is well coated in oil and spices.
- Roast the vegetables in the fully preheated oven for 40 minutes, or until the vegetables are slightly wilted and the edges have a nice brown color. Stir the vegetables half way through the roasting time to make sure everything gets even exposure to the hot air.
- After removing the vegetables from the oven, squeeze fresh lime juice over top. Sprinkle chopped cilantro over the vegetables. To serve the fajitas, scoop a small amount of the roasted vegetables into each tortilla and add a slice of avocado.
See how we calculate recipe costs here.
Equipment
- Enamelware Sheet Pan
Notes
Nutrition
How to Make Sheet Pan Portobello Fajitas – Step by Step Photos
Begin by preheating the oven to 400ºF. In a small bowl, stir together 1 Tbsp chili powder, 1/2 tsp chipotle powder, 1/2 tsp onion powder, 1/2 tsp garlic powder, 1 tsp cumin, 1 tsp sugar, and 1/2 tsp salt.
I used 8 oz. portobello caps (2-3 depending on their size), two bell peppers (any color), and two yellow onions for my fajitas.
Slice the vegetables into strips about ¼-inch wide. I also cut the portobello strips in half, so the pieces aren’t quite so large. Place the sliced vegetables on a large sheet pan.
Drizzle 3 Tbsp olive oil over the vegetables, then sprinkle the prepared fajita seasoning over top.
Use your hands to toss the vegetables in the oil and spices until everything is evenly coated, then make sure the vegetables are spread out over the baking sheet in an even layer.
Roast the vegetables in the preheated oven for 40 minutes, or until they are slightly wilted and have browned on the edges. Stir the vegetables halfway through the roasting time to make sure everything gets even exposure to the hot air.
After roasting, squeeze lime juice over the vegetables and top with chopped cilantro.
To serve, scoop a small amount of the fajita vegetables into each small tortilla and add a slice of fresh avocado.
Seriously, these Chipotle Portobello Oven Fajitas are probably one of my favorite vegan recipes!
SO good and easy.
I just made this. It was really good. I used sour cream instead of avocado.
Thank you so much. I have all of the ingredients except the portobellos. I am going to make this today with the hopes that it will still taste as delicious as you’ve made it look here. Thanks!
Hey Beth! I was thinking of suprising an Vegan friend with this recipe, it looks like a great/easy to make recipe, I am just wondering if you have something good to substitute out the Peppers for?
Cheers from Sweden
Hmmm, I don’t really know what you could use in their place. Peppers are a main part of the classic fajita filling, so it wouldn’t quite be the same without them. Technically you could do just about any vegetable, it just wouldn’t be very fajita-like. :)
These were rediculously good. The chipotle chili powder really made all the difference. This will definitely enter our regular meal rotation – but we’ll probably add at least one more portabella mushroom. Thanks for another excellent recipe!
Can you freeze this recipe?
This one won’t be quite as good if it has been frozen and thawed. The vegetables will probably get a bit watery, which is not what you want with fajitas. :(
We love this recipe. It’s on frequent rotation in my house. We usually only get 3 servings because we can’t stop picking at the roasting pan, but who cares? More veggies, right? Thanks, Beth, for yet another winner.
This was a great recipe! I really liked it with some avocado and sour cream. Yummy yummy! Would love to see a recipe for a portobello mushroom burger one day :) Thanks for all your great recipes! Your site has been 70-80% of my diet for the past year. :)
These were so yummy and easy! The leftover veggies were even more delicious the next day and were easily repurposed into quesadillas. I am making these again and looking forward to making burrito bowls with the leftovers.
I’m planning on making these tonight. They look really good and I’ve been looking for a way to try portobello mushrooms in a different way – this looks really good!
Tell me, do you think I could sub out the spice mixture for taco seasoning? I don’t have chipotle powder or garlic powder, but I do have seasoning. I’ll just add in the sugar and salt with it. Do you think that would work?
Thanks again for all your posts – they’re wonderful!
Yes, I think that would still be delicious. :)
These are so ridiculously good! Probably our favorite from your site so far (and that’s saying a lot, as we’ve been meal planning and eating pretty much off your site alone for the last 6 months).
DELISH. Thank you!
I love this recipe! I’m a huge fajita fan and I’m vegetarian. Thanks so much. Made it twice now.
You use garlic powder in the step by step but not the simple recipe. Im assuming it was forgotten.
Love the website!!!
Thanks for catching that! Fixing now.
I could kiss you. I made this recipe this afternoon. I just ate it. It was so easy and so tasty. I used chicken thighs ( on sale) and portobellos ( loose, cheaper by the oz) and a HEB ( Texas chain of grocery store) Grill Masters, chipotle and garlic seasoning mix it was on sale for a DOLLAR and had all the ingredients in your spice mix minus sugar and cornstarch, Plus onion powder. So compared to the 7.00 bottle of chipotle powder I went with that. I can’t wait to make this again, for dinner, during the week lunches, or parties. THANK YOU ! I did add a tiny tiny bit of honey to one to make up for there not sugar. Both turned out nicely, I also used red peppers so thats probably why it didn’t need any sugar.
I was hesitant to try this recipe because I’m not a huge fan of mushrooms, but it was delicious. I highly recommend it.