These vegan fajitas with marinated Portobello steak are the most flavourful, drool-worthy fajita recipe out there! Take standard Portobello fajitas to the next level by marinating Portobello mushrooms overnight with onions and peppers so they soak up all the amazing flavour. Served with homemade vegan sour cream, you will want to go back for seconds, and thirds, and fourths!
I love this recipe because it’s easy to make, and excluding the marinating time, very quick. To make this recipe you will first need some homemade taco seasoning!
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Add Protein to Vegan Fajitas
This vegan fajita recipe is a delicious, but low-protein option. While Portobello mushroom “steak” provides some protein, it’s likely not an adequate amount for most people.
It’s okay to occasionally eat a lower protein meal, but I don’t recommend it to be a routine, as you will likely start missing some important nutrients that come along with that plant-based protein.
Serving these vegan fajitas with my homemade vegan sour cream recipe adds a bit of protein because it’s made from cashews and tofu. However, this still won’t make it a high protein meal.
If you’re looking for a protein boost, the easiest way is adding black beans into your marinated fajitas. Alternatively, you could crumble some tofu and add it to the marinating Portobello mushrooms.
Regardless, this vegan fajita recipe is super tasty.
How to Serve your Marinated Vegan Fajitas
I like to serve any type of vegan fajita with sour cream, leafy greens, and avocado. The sour cream adds a fresh note to the rich and flavourful marinated fajita mix, and the leafy greens add a nice crunch.
If you’re a cilantro-lover like me, chopped cilantro is the perfect addition to these marinated fajitas! You can always make some tasty guacamole to go with these vegan fajitas as well. Guacamole is a great alternative to sour cream if you prefer.
Don’t forget to quickly whip up a batch of taco seasoning before you get started on your fajitas!
I hope you enjoy this recipe. You may also be interested in my delicious sheet pan jackfruit fajitas!
Vegan Fajitas with Marinated Portobello Steak
- Baking tray
- Silicone baking mat
- Large well-sealed container
- Cutting Board
- 6 medium-sized Portobello mushrooms
- 1 medium onion
- 3 medium bell peppers can use a variety of colours
- 3 tbsp oil (I use olive or avocado)
- 5 tbsp soy sauce can use tamari if gluten free
- 1 tbsp vegan Worcestershire sauce
- 1 tbsp lime juice can use 1 tsp of apple cider vinegar if you don’t have limes
- 1 tbsp taco seasoning
- 1 ½ tbsp nutritional yeast
- Slice the mushrooms, peppers, and onion and place into a large container with a lid. I like my mushrooms and peppers slice fairly thick, and the onions sliced thinly, but you can go by your own preferences.
- Toss the remaining ingredients (3 tbsp oil, 5 tbsp soy sauce, 1 tbsp vegan Worcestershire sauce, 1 tbsp lime juice, 1 tbsp taco seasoning, and 1 ½ tbsp. nutritional yeast) onto the sliced vegetables.
- Place a lid on the container and shake the vegetables well so the marinade covers all slices. Place into the fridge to marinate overnight if possible (aim for at least 2 hours).
- When the vegetables have marinated and you are ready to cook, preheat the oven to 400 °F.
- Place an even layer of vegetables on 2-3 baking trays. Bake for 30 minutes, tossing halfway through, until the vegetable edges are cooked and crisping. Some people prefer more “blackened” fajitas; you can achieve this by leaving the vegetables in the oven for longer (an additional 15-20 minutes) or turn your broiler on and place each tray (one at a time) under the broiler for 2-3 minutes. Do not leave your oven unattended with the broiler on – food can burn within a minute or two so keep a very close eye on things if you choose to do this.
- While the fajitas cook, prepare the toppings and other ingredients to serve.