Easy sheet pan vegetarian fajitas recipe! You won’t miss the meat in these portobello veggie fajitas cooked on a sheet pan in the oven. Perfect for a weeknight dinner!
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Hey, Rhubarbarians! Sharing one of our favorite easy weeknight dinners: 30-minute sheet pan vegetarian fajitas!
We love our quick weeknight meals. Here's our ultimate list of easy weeknight vegetarian recipes!
These are quick, fuss-free, and best of all absolutely delicious. You won't miss the meat thanks to the "meaty" portobello mushrooms. We think these are the BEST veggie fajitas! A tex-mex fave that our family loves to customize with lots of toppings.
Fajitas are traditionally a tex-mex dish made with strips of meat, peppers, and onions. We took that idea and made our version of vegetarian fajitas by replacing the meat with portobello mushrooms.
Why this recipe works: the portobellos add a "meaty" texture and flavor to the fajitas veggies! Everything is quickly coated in a homemade fajita sauce and roasted together on a sheet pan for a flavorful, no-fuss dinner.
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Sheet pan fajita veggies
Bust out your sheet pan because that's almost all you need for this dinner! All of the fajita veggies get cooked on a sheet pan in the oven. So simple.
We slice up portobello mushrooms, bell peppers, and onion, and toss those in a simple homemade fajita seasoning sauce. Then we bake them in the oven and voila! Dinner is done!
Since everything is cooked on one pan in the oven, you can focus your energy on preparing your toppings. Or heck, maybe even relax a bit!
It's easier than you think to make your own corn tortillas. Check out our homemade corn tortillas recipe!
Ingredients and equipment
See the recipe card at the bottom of this article for full ingredients and instructions.
Ingredients:
- Portobello mushrooms. Check out this beginner's guide to portobello mushrooms for everything you need to know
- Bell peppers: we like orange and yellow! But any color you prefer will work
- Onion: red onion or yellow onion
- Neutral oil: we like grape seed oil for it's high smoke point. Vegetable oil and canola are good alternatives
- Seasonings: we make our fajita seasoning with chile powder, cumin, coriander, smoked paprika, garlic powder, and salt
- Tortillas: corn or flour, your choice
- Fajita toppings: we like guacamole, sour cream, cilantro, tomato, and cheese
Equipment:
- Oven
- Cutting board
- Sharp chef's knife
- Large and small bowl
- Measuring spoons
- Whisk or spoon
- Tongs
- Sheet pan
Homemade fajita seasoning
You won't believe how easy it is to make your own fajita seasoning and fajita sauce! Full ingredients and instructions are listed in the recipe card at the bottom of this article.
We start by creating an easy fajita seasoning blend. Combine chile powder, cumin, coriander, smoked paprika, garlic powder, and salt. Mix that with a decent amount of oil to create a sauce that will coat all of your veggies.
We just mix it together in a small bowl and then pour it over the veggies and mix with tongs. But, you could also put it in a mason jar with a tight fitting lid and shake until combined.
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How to cut the veggies
To make fajitas, you have to cut your veggies into strips!
We like to cut our veggies into ½" thick strips, which we think is just the right size. Not too thick, not too thin. Feel free to slice your veggies into thinner or thicker strips. Note that thicker strips may take a bit longer to cook in the oven.
- The portobello mushrooms: remove the stem and gently wash them well. Pat them dry before cutting. Cut them into ½" strips.
- The bell peppers: Cut the peppers in half and then cut out the stems, seeds, and pith. Cut the peppers lengthwise into ½" strips.
- The onion: Peel the onion. Cut the onion in half width wise, so not cutting into the root and stem. Flip the onion cut side down on the cutting board and cut off the root and stems on the end. Slice into ½" slices width wise. Here's a great resource for how to slice an onion!
Step by step instructions
See the recipe card at the bottom of this article for full ingredients and instructions.
- Preheat your oven and get all of your veggies prepped and sliced.
- Place the veggies in a large mixing bowl or onto the sheet pan (if the sheet pan is large enough to toss the veggies).
- Prepare your fajita seasoning sauce (see instructions above or in the recipe card).
- Pour the fajita sauce over the veggies and gently toss to coat with tongs or your hands.
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- Spread the veggies evenly on the sheet pan and place in the preheated oven.
- Cook the veggies in the oven for 20 minutes, tossing them halfway through.
- While the veggies are cooking, prepare your toppings.
- To serve, place some of the veggies in the center of a tortilla and top with the toppings of your choice.
Serving suggestions
We love fajitas because they are very versatile! We like to serve fajitas as an entree with lots of fajita toppings and some beans, rice, and/or corn on the side.
Our favorite fajita toppings:
- Guacamole
- Sour cream
- Cheese
- Tomato
- Fresh cilantro
- Pepitas
To make the fajitas a meal without any sides, try making large fajitas (with larger tortillas) and add black or pinto beans, rice, and corn!
Recipe tips and substitutions
- Don't overcrowd your sheet pan or the veggies will steam rather than roast. You can fit a lot on a large sheet pan, but don't pile the veggies on.
- If your sheet pan isn't very large, toss the veggies with the fajita sauce in a large bowl. This is much easier than tossing a lot of veggies on a sheet pan.
- If you can't find portobello mushrooms, go ahead and use cremini or button mushrooms. Rather than 3 portobellos, go for about 15 cremini mushrooms. Slice them into ½" thick slices.
- This recipe is vegan with the exception of the topping suggestions. For a vegan option, leave out the sour cream and cheese or use vegan alternatives.
- For a gluten-free option, use corn tortillas or gluten-free tortillas.
- We like to use small tortillas and one serving is equivalent to 2 small fajitas. Feel free to use larger tortillas and make larger fajitas.
- To use frozen peppers, make sure they are already cut into strips. We recommend baking the frozen peppers until they are defrosted and then tossing with the seasoning mixture along with the other veggies.
- To use store bought fajita seasoning, just make sure you like the flavor. Combine the seasoning with the oil to create the sauce mixture to coat the veggies.
Prep ahead and meal prep
- Prep ahead: the veggies can be sliced ahead and kept in the refrigerator for a couple of days until ready to cook. The fajita sauce can be made ahead of time and kept in an air tight container on the counter.
- Meal prep: This recipe is great for meal prep! After cooking, store the fajita veggies separately from the toppings and tortillas. Add some beans, rice, and/or corn to your meal prep container for a more complete meal.
Storing and freezing
- Storing: we don't recommend storing assembled fajitas as leftovers. However, the fajita veggies make great leftovers. Store any leftover fajita veggies in a well sealed container in the refrigerator for up to 5 days. The portobello mushrooms will become more rubbery each day they are left in the fridge, so they are best eaten quickly. Reheat the fajita veggies in the microwave or oven and then place in a tortilla and top with your fajita toppings.
- Freezing: We don't recommend freezing assembled fajitas. However, the fajita veggies can be frozen. Freeze fajita veggies in a well sealed freezer safe container for up to 3 months. The texture of the portobello mushrooms might be rubbery after freezing, so we recommend defrosting the fajita veggies before reheating in the oven at 400 degrees F.
FAQs
Yes! As long as they are already sliced into strips. We recommend baking the frozen peppers until they are defrosted and then tossing with the seasoning mixture along with the other veggies.
Sure! Just make sure you like the flavor. Combine the seasoning with the oil to create the sauce mixture to coat the veggies.
This recipe is vegan with the exception of the topping suggestions. For a vegan option, leave out the sour cream and cheese or use vegan alternatives.
This recipe is gluten-free with the exception of the tortillas. Use corn or tortillas or gluten-free tortillas that you like.
More recipes to try:
- 20-minute broccoli cheddar quesadillas (vegetarian)
- Pinto bean and pecan taco lettuce wraps (vegan)
- Crispy vegan tofu tacos with cilantro cream sauce (vegan)
- Sheet pan butternut squash and black bean tacos (vegan)
- Corn and black bean tacos with smoky sour cream (vegetarian)
Did you make this recipe? Leave us a review and star rating in the comments below! We read every single review and appreciate your feedback.
Recipe
Easy sheet pan vegetarian fajitas recipe! You won’t miss the meat in these portobello veggie fajitas cooked on a sheet pan in the oven. Perfect for a weeknight dinner!
- 3 medium portobello mushrooms, sliced into ½" slices stems removed and cleaned
- 3 medium bell peppers, sliced into ½" slices stems and seeds removed
- 1 medium red or yellow onion, sliced into ½" half moons (see notes) peeled and root and stem ends removed
- ½ medium lime
- 3 Tablespoons grape seed oil or vegetable oil
- 1 ½ Tablespoons chile powder
- 1 Tablespoon ground cumin
- 1 Tablespoon ground coriander
- ½ teaspoon smoked paprika
- ½ teaspoon garlic powder
- ½ teaspoon salt
- 12 small tortillas, corn or flour
- guacamole, sour cream, cilantro, tomato, cheese
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Preheat the oven to 400° F.
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Prep your veggies and place them in a large mixing bowl.
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In a small bowl or jar, combine the oil, chile powder, cumin, coriander, smoked paprika, garlic powder, and salt. Stir until you form a sauce. Pour the sauce over the veggies and gently toss to coat with tongs or your hands.
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Spread the veggies evenly on the sheet pan and bake in the oven for 20 minutes, tossing the veggies halfway through. If the veggies are not cooked through enough for you liking, bake for another 5 minutes.
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Squeeze half of a lime over the veggies and gently toss. Taste and season to your liking with salt and pepper.
To cut the onion slices: after peeling, cut the onion in half width wise, so not cutting along the root and stem. Then flip the onion cut side down on the cutting board and slice into ½" slices.
Nutritional information does not include fajita toppings.
- Don't overcrowd your sheet pan or the veggies will steam rather than roast. You can fit a lot on a large sheet pan, but don't pile the veggies on.
- If your sheet pan isn't very large, toss the veggies with the fajita sauce in a large bowl. This is much easier than tossing a lot of veggies on a sheet pan.
- If you can't find portobello mushrooms, go ahead and use cremini or button mushrooms. Rather than 3 portobellos, go for about 15 cremini mushrooms. Slice them into ½" thick slices.
- This recipe is vegan with the exception of the topping suggestions. For a vegan option, leave out the sour cream and cheese or use vegan alternatives.
- For a gluten-free option, use corn tortillas or gluten-free tortillas.
- We like to use small tortillas and one serving is equivalent to 2 small fajitas. Feel free to use larger tortillas and make larger fajitas.
- To use frozen peppers, make sure they are already cut into strips. We recommend baking the frozen peppers until they are defrosted and then tossing with the seasoning mixture along with the other veggies.
- To use store bought fajita seasoning, just make sure you like the flavor. Combine the seasoning with the oil to create the sauce mixture to coat the veggies.
If you make this recipe, please let us know on social media or in the comments below! Leave a star rating in your comment or tag us on Instagram with #Rhubarbarians
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