Sheet Pan Portobello Mushroom Fajitas

Quick sheet-pan fajitas with portobello mushrooms, bell peppers, and a homemade fajitas spice mix. Serve on warmed small tortillas with guacamole, salsa, sour cream, and black beans.

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Prep Time 10

Cook Time 40

Total Time 50

Course Main

Cuisine Mexican

Servings 6 servings

Equipment

Regular parchment paper
Microwave tortilla warmer
Metal taco holder

Ingredients

6 Small tortillastry ourflourless red lentil tortillas
1 Red onion medium
3 Bell pepper red, yellow, green
2 Large portobello mushrooms
2 +1/2 TbspFajitas spice mixsee below
2 TbspOlive oil
Salt and Pepper to taste
1/2 tspHot chili powder or flakes
2 TbspSweet smoked paprika powder
1 +1/2 tspGround cumin seeds
1 +1/2 tspGarlic powder
1 +1/2 tspOregano
6 TbspGuacamole
6 TbspSalsa
6 TbspSour creamtry ourvegan sour cream
6 TbspBlack beans

Instructions

Preheat oven to 430°F (220°C). Line a sheet pan with parchment paper.
Slice the red onion into 1/4-inch (4–5 mm) wide slices. Wash and slice the three bell peppers (red, yellow, green) into 1/4-inch (4–5 mm) wide strips. Clean the portobello mushrooms with a damp towel if needed, remove the stems, and slice the caps into 1/4-inch (4–5 mm) wide strips.
In a small bowl, mix the listed spices to make the fajitas spice mix: 1/2 tsp hot chili powder or flakes, 2 Tbsp sweet smoked paprika, 1 1/2 tsp ground cumin seeds, 1 1/2 tsp garlic powder, and 1 1/2 tsp oregano. From that mixture, set aside 2 1/2 Tbsp total and divide it into two equal portions (you will use one portion now and the other after the first roast). Reserve any remaining spice mix for another use.
Spread the sliced onion, bell peppers, and mushroom strips in a single layer on the prepared sheet pan (use two pans or overlap slightly if necessary). Drizzle with the 2 Tbsp olive oil, sprinkle with salt and pepper to taste, and add one of the two equal portions of the 2 1/2 Tbsp fajitas spice mix. Toss everything with tongs until evenly coated.
Roast the vegetables in the preheated oven for 10 minutes.
Remove the sheet pan, use tongs to turn the vegetables so they cook evenly, then sprinkle the remaining half of the reserved fajitas spice mix over the vegetables. Return the pan to the oven and roast for 10 more minutes, or until the vegetables are tender and slightly charred at the edges.
While the vegetables finish roasting, warm the 6 small tortillas: wrap them in foil and place in the oven for the last 2–3 minutes, or warm individually in a dry skillet for about 20–30 seconds per side.
To assemble, place a few mushroom strips and a portion of the roasted bell pepper and onion in the center of each warmed tortilla. Divide the 6 Tbsp guacamole, 6 Tbsp salsa, 6 Tbsp sour cream, and 6 Tbsp black beans evenly among the 6 tortillas (about 1 Tbsp each of guacamole, salsa, sour cream, and black beans per tortilla). Fold and serve immediately while hot.

Notes

Use a sheet pan with parchment paper.We recommend using a sheet pan because it has sides. If you use a baking sheet, the juices from the veggies during roasting might not flow off of it.
Cut veggies into equal strips.This is to make sure the vegetables are ready at the same time.
Place veggies in batcheson the sheet pan. They will be easier to mix, match, and serve if they are grouped.
Hot and sweet together?– If you prepare the veggies for kids or people who don’t like spicy food, roast hot chili peppers separate from all other veggies. If you roast hot chili peppers and bell peppers together, the juices of the hot chili peppers may make the sweet bell peppers also spicy and hot.
Other ways to make fajitas veggies.After preparing and cutting your veggies, you can use other ways to get them ready like 1) Sautee them in a cast-iron skillet orgrill panor griddle or 2) Grill them inaluminum foil drip panson your BBQ.