Oven Baked Portobello Mushroom Tacos

Mushrooms for President

I’m one of those people who think “mushrooms make nearly every recipe better” – the chewy texture and earthy flavor are the perfect ingredient for meal time. These portobello mushroom tacos make for the mushroom meal of my dreams. Each taco is a perfect bit of mushroom, black beans, avocado, pickled red onion, cilantro, and cotija.  It’s a mix of tangy, earthy, creamy, herby, and savory flavors that I love.

While we’re not a vegetarian household, I do try to plan one or two vegetarian meals per-week.  They make our weekly meals more interesting, by having a wider variety of proteins to eat throughout the week, and vegetables, legumes, and grains are typically cheaper than meat, which saves us some money on our grocery bill. If it’s not something you’ve tried, you absolutely should!  Do a test run for a week (and add this recipe to the mix) and see how you enjoy it!

Tips For Making This Portobello Mushroom Taco Recipe

If you plan on making these Portobello Mushroom Tacos, here are a few tips to make them extra special:

• After cleaning your portobello mushrooms, make sure they are completely dry before baking them.  Otherwise, there may be too much moisture and the mushrooms may come out soggy.
• Speaking of avoiding soggy mushrooms, use as fresh of portobello mushrooms as you can.  They’ll taste better, as they’ll be plumper and more full of flavor.  Older mushrooms may shrivel up faster in the oven.
• When making the pickled red onions, I recommend doubling the recipe if you love adding this garnish to other dishes.  It will keep in the fridge for several weeks if left in the vinegar, and only gets better with time!
• If you can’t find cotija cheese at your grocery store, feta cheese is a great substitute.  It has a similar taste and texture, giving you that creamy, crumbly, tang the cotija adds.
• If meal prepping, make a small pan of rice while you prepare the rest of the ingredients. In leftover containers, add a bit of rice and top with the black beans, portobello mushrooms, avocado, cotija, and cilantro. Serve with tortillas on the side if desired, and you have a delicious portobello burrito bowl.
• Keep the sides simple, so you can focus on the taco components while you’re cooking.  Make a bag of microwave rice, buy a pre-made elote from the grocery store, or throw in a tray of frozen french fries while you bake the portobellos.  You’ll have a full meal prepared, without much effort!

Recipe Details

Prepare and Bake the Portobello Mushrooms

This recipe has several components, which may be intimidating, but each component comes together in a matter of a few minutes.  In the time it takes the portobello mushrooms to cook, you’ll be able to prepare the pickled onions, mashed avocado, and black beans ready to go.  In about 30-minutes, you’ll have a taco night sure to impress your whole family or friends.

To start, you’ll prepare and bake the portobello mushrooms.  A simple taco seasoning blend and olive oil will coat the outside of each mushroom cap.  You’ll bake the mushrooms, first cap-side down for about 15 minutes.  Then, flip each mushroom cap and bake for another few minutes, until the mushrooms are baked through.  Slice each mushroom cap to about a half-inch thick and you’ll be ready to add them to your tacos!

Make the Taco Toppings

While the mushrooms bake, you’ll mash some avocado with lime juice and salt, quick pickle some red onion slices, and warm and mash some black beans with cumin powder. Each of these components come together in a matter of a few minutes.

The “cheats” pickled red onion is the simplest way to make pickled red onions, without really pickling them.  It requires no heat, minimal wait time, and results in a tangy red onion. It’s a trick I learned years ago that I use all the time, as it only needs to sit for 15 minutes or so.  By doing it early in the process, you’ll have a pickled red onion ready to go when the rest of your meal is prepared!

Assemble and Enjoy

To assemble these portobello mushrooms tacos, you’ll layer the black beans, sliced mushrooms, avocado, and pickled red onions. A garnish of fresh cilantro and crumbled cotija cheese and you’ll be ready to eat!

If you like the sound of this recipe, you should also check out these other delicious Tex-Mex inspired recipes:

• Elote Chicken Burrito Bowl
• Baked Black Bean Corn Feta Dip
• Roasted Salmon with Avocado Mango Cucumber Salad

‍If you make these portobello mushroom tacos, be sure to leave a comment or give this recipe a rating – I can’t wait to hear how it goes. As always, tag me on Instagram, TikTok, or Facebook in your photos. It makes me feel like we’re getting to cook together!

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Oven Baked Portobello Mushroom Tacos

Author: Laura Wilkins Cooking Method: Baked Cuisine: Mexican Courses: Tacos

Difficulty: Intermediate Prep Time 5 mins Cook Time 25 mins Total Time 30 mins

Cooking Temp: 400  °F Servings: 4

Best Season: Suitable throughout the year

Dietary:

G Gluten Free N Nut Free V Vegetarian

Description

Simple, yet so tasty, these portobello mushroom tacos are layered with flavors. It’s a perfect weeknight taco dinner, with oven-baked portobello mushrooms, mashed black beans, avocado, pickled onions, and cotija coming together in about 30 minutes.

Ingredients

Scale

1/2x 1x 2x 3x

• 4 large portobello mushroom caps
• 1 tbsp plus 1 teaspoon olive oil, divided
• 1 tsp garlic powder
• 1 tsp onion powder
• 1 ¹⁄₂ tsp cumin powder, divided
• 1 tsp chili powder
• 1 red onion
• ¹⁄₂ cup red wine vinegar
• 2 tsp salt, divided, plus 1 pinch to taste
• 2 limes
• 1 avocado
• 1 can black beans, rinsed well
• 1 tsp black pepper
• 8-10 taco-sized flour or corn tortillas
• Cilantro and crumbled cotija for topping

Instructions

Prepare and Bake the Portobello Mushrooms

1. Preheat the oven to 400°F and line a large baking tray with aluminum foil.

2. In a dish, drizzle 1 tablespoon of olive oil over the portobello mushroom caps. Mix 1 teaspoon garlic powder, 1 teaspoon onion powder, 1 teaspoon cumin powder, 1 teaspoon chili powder, ½ teaspoon salt, and ½ teaspoon black pepper in a small bowl until evenly distributed.

3. Sprinkle the seasoning mix over the mushroom caps and use a spoon or your hands to massage the oil and spices into the skin of the mushrooms. 

4. Arrange the mushroom caps on the prepared baking sheet, stem side down.  Bake for 15 minutes.

5. Remove from the oven and flip the mushroom caps to stem-side up. Continue baking for another 5-10 minutes, until the mushrooms are baked through to your liking.

6. Slice into ½ inch slices and set aside until you’re ready to assemble your tacos.

Prep the Cheats Pickled Red Onion

1. Thinly slice the red onion and add to a small bowl.

2. Pour ½ cup red wine vinegar, 1 teaspoon salt, and juice from ½ a lime. Stir until all red onion slices are covered in vinegar.  Set aside and let marinate while you prepare the remaining components.

3. Stir occasionally between making the rest of the components, to ensure all slices are in contact with the vinegar and lime juice.

Prepare the Mashed Avocado

1. In a small bowl, add the avocado, juice from 1 lime, and a pinch of sea salt.  Mash the avocado until it’s smooth and creamy. Set aside.

Heat and Mash the Black Beans

1. In a small saucepan, add the rinsed black beans, ½ teaspoon cumin powder, ½ teaspoon salt, ½ teaspoon pepper, 1 teaspoon olive oil, and 1-2 teaspoon water.  Place over medium-low heat.

2. Stir occasionally and mash with a wooden spoon.  Let warm for about 5 minutes until it’s completely warmed through and mashed to your liking.

Assemble the Portobello Mushroom Tacos

1. Wrap the tortillas in a damp paper towel and microwave for 15-20 seconds to soften them slightly. 

2. Scoop a spoonful of mashed black beans onto each tortilla. Arrange 2-3 slices of the baked portobello mushrooms over the black beans on each taco.

3. Add a spoonful of mashed avocado on the top. Arrange a few slices of pickled red onions over the avocado and garnish with freshly torn cilantro and crumbled cotija cheese.

4. Serve immediately and enjoy!