How To Cook & Season Vegetables For Fajitas

January 13, 2025
sizzling fajita on skillet surrounded by different garnishes

Discover the secrets to creating the ultimate sizzle in your kitchen with our comprehensive guide on how to cook and season vegetables for fajitas!


Vegetables are a key part of any fajita recipe and add colour, flavour, and a satisfying crunch. However, if you haven’t made fajitas before or not for a while, you may be wondering how to cook and season the vegetables for your fajitas so that they’re just right! In this guide, we’ll explore the most popular vegetables used in fajitas, how to cut and prepare them, cooking and seasoning techniques, and even tips for preserving leftovers.

The Best Vegetables For Fajitas

Fajitas are all about creating a rainbow of flavours and textures. While bell peppers and onions are fundamental to the dish, the versatility of fajitas allows you to easily adapt ingredients to suit your tastes. Here are some of the most popular options:

  • Bell Peppers (Red, Yellow, Green): Bell peppers are the quintessential fajita vegetable. Each colour adds a unique balance of sweetness and crunch and is what generally gives fajitas their vibrant appearance.
  • Onions (Red or White): Onions add a savoury depth and a natural caramel sweetness when cooked. Red onions provide additional vibrancy, while white onions offer their classic sharpness.
  • Mushrooms (Portobello or Button): Ideal for vegan and vegetarian fajitas, mushrooms are filling and deliver a hearty, meat-like texture.
  • Courgettes: The fresh flavour and soft texture of courgettes makes them a great addition to fajitas, especially during the summer months.
  • Sweet Potatoes: For a creative twist, roasted sweet potato strips can bring a natural sweetness and creaminess to fajitas.
  • Seasonal Additions: Experiment with roasted cauliflower, corn, or asparagus when in season. These less-conventional options can help you create something unique, keeping your fajita dishes fresh and varied!

It’s clear to see that fajitas celebrate flexibility. Plus, they’re great for using up any leftover vegetables you might have in your fridge! Next up we’ll explore how to best cut the peppers and onions for your fajitas.

How To Cut Peppers And Onions For Fajitas


Properly cutting your vegetables will ensure they cook evenly and enhance your fajita’s presentation. Follow these step-by-step guides to prepare your peppers and onions effectively and efficiently:

a hand slicing a red onion with knife on a wooden cutting board

How to Cut Onions for Fajitas

  1. Wash the onions and your hands thoroughly.
  2. Slice the onion in half from root to tip and peel away the papery skin.
  3. Lay the onion flat side down on a clean chopping board.
  4. Slice the onion lengthwise into thin strips, following the onion’s natural grain for the best texture.
a hand slicing a red bell pepper with knife on a wooden cutting board

How to Slice Peppers for Fajitas

  1. Wash hands and rinse the peppers under cold water to remove dirt or residue.
  2. Cut off the top and bottom of the pepper, then make a clean slit down one side.
  3. Open the pepper flat, removing the seeds and internal white membranes.
  4. Slice into even strips about 1cm wide for uniform cooking.

Pro Tip: Leftover raw vegetables can be stored in an airtight container in the fridge and used within three days – allowing you to easily cook up more fajitas the following day!

How To Cook Fajita Vegetables


In this section we’ll teach you how to cook fajita vegetables using an easy technique that’ll help you achieve a tender, lightly charred finish while enhancing natural flavours. Simply follow these easy steps:

a hand pouring oil into red frying pan on a stovetop

Cooking Fajita Vegetables

  1. Heat Your Pan: Use a large cast-iron skillet or non-stick frying pan. Preheat it on high to achieve that sizzling sear.
  2. Add Oil: Use a tablespoon of vegetable oil to prevent sticking.
  3. Sauté: Start with your onions, cooking for 2–3 minutes to bring out their sweetness. Then, add peppers and cook for another 2–3 minutes, stirring occasionally for even charring.
  4. Add Mushrooms or Other Veggies: Introduce mushrooms or other soft vegetables toward the end to preserve their texture.

How To Season Fajita Vegetables

Seasoning is the magic ingredient that will truly give your fajitas that wow factor! Here’s how to season your fajita vegetables:

  1. Sprinkle your chosen fajita seasoning over your cooked veggies and toss to coat evenly.
  2. For a fresh twist, finish with chopped coriander, a squeeze of lime, or a pinch of smoked paprika for depth.

With our seasonings you can opt for a variety of flavours from spicy to BBQ. Check them out below:

Put Your Fajita Making Skills To The Test


Now that you’ve learned all there is to know about cooking and seasoning vegetables for fajitas, it’s time to put the techniques to the test! Full of veg - our Vegan Portobello Mushroom and Pepper Fajitas are the perfect dish to start with.

Vegan Portobello Mushroom & Pepper Fajitas

Vegan Portobello Mushroom & Pepper Fajitas

In this recipe savoury mushrooms, peppers and onions take a spin in the skillet and join forces with a quick guacamole for a fabulous vegan fajita feast made in just 40 minutes!


Recipe Name

Vegan Portobello Mushroom & Pepper Fajitas

Total Time

40 minutes

Spice Level

Mild

Servings

8

Ingredients

  • 2 ripe avocados, stone removed, peeled and chopped
  • 2 tablespoons freshly chopped coriander, plus extra to garnish
  • Juice of 1 lime, plus extra wedges, to serve
  • 2 tablespoons vegetable oil
  • 1 onion, thinly sliced
  • 1 red pepper, deseeded and sliced
  • 1 yellow pepper, deseeded and sliced
  • 6 portobello mushrooms, cut into 5mm slices
  • 1 Old El Paso™ Smoky BBQ Fajita Kit

Preparation

  1. Place the avocados, chopped coriander and half the lime juice in a bowl and roughly mash together with a fork. Season with salt and freshly ground black pepper. Set aside.
  2. Heat half the oil in a large non-stick frying pan over a high heat. Add the onion and peppers and cook for 2-3 minutes until beginning to soften. Add the rest of the oil and the mushrooms and cook for 1 minute, then stir in the seasoning mix from the fajita kit and the remaining lime juice and cook for a further 2-3 minutes until the mushrooms are tender.
  3. Heat the tortillas to pack instructions. Place some of the mushroom and pepper mixture, a drizzle of salsa and a couple of spoonfuls of guacamole onto each tortilla. Garnish with extra coriander and roll up. Serve with the extra lime wedges.

Expert Tips

  • Try not to stir the mushrooms too much during cooking as the slices can break apart.
  • You may need to cook the mushroom and pepper mixture in two batches if you don’t have a large enough frying pan.
  • Cooking Vegan? Always read labels to make sure each recipe ingredient is vegan. Products and ingredient sources can change.

Made With...

Discover More Fun Fajita Recipes

There you have it, an easy guide and recipe showing you how to cook and season vegetables for fajitas! Why not make Fajita Fridays a regular event in your household? Fun and quick to make, they’re the perfect dish to end the week and we have plenty of easy fajita recipes you can try here!

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