Chicken Fajitas with Onions

The first time I made sheet pan fajitas, I stood in front of the oven watching through the glass door as the peppers turned from bright and crisp to tender and charred at the edges. My kitchen filled with that smoky, cumin-scented perfume that somehow makes everything feel like a celebration, even on a random Tuesday. I remember pulling the pan out and realizing dinner was ready with almost zero cleanup, which felt like discovering a cheat code for weeknight cooking. Now this is the recipe I turn to when I want something that feels like restaurant food but requires about as much effort as making toast.

Last summer my sister came over exhausted from a twelve hour shift and I threw these fajitas together while she collapsed on the couch. When she took her first bite, her eyes actually lit up and she asked if I had been secretly cooking all afternoon. That moment of someone feeling taken care of without you having to exhaust yourself is exactly why this recipe lives in permanent rotation at my house.

Ingredients

• Chicken breast: Cutting against the grain into thin strips helps them cook quickly and stay tender, plus more surface area means more seasoning in every bite
• Bell peppers: Mixing colors creates a beautiful presentation and each variety brings its own sweetness level to balance the spices
• Red onion: These become naturally sweet as they roast, mellowing out the spices and adding a perfect caramelized bite
• Chili powder and cumin: This classic combination gives you that authentic Tex Mex flavor without needing to hunt down specialty ingredients
• Smoked paprika: The secret ingredient that tricks everyone into thinking these came off a grill even when they are oven roasted
• Fresh lime: That final squeeze of acid right before serving wakes up all the flavors and makes everything taste brighter

Instructions

Get your oven ready:

Crank that oven to 425°F and line your sheet pan with parchment paper because you will thank yourself later when cleanup takes thirty seconds.

Mix the magic seasoning:

Whisk together all those spices with the olive oil until you have a reddish brown paste that smells absolutely incredible.

Coat everything:

Toss the chicken strips and vegetables right in the bowl with the marinade, using your hands to make sure every single piece is covered in those spices.

Spread it out:

Arrange everything in a single layer on your prepared sheet pan, giving the chicken and vegetables some room to breathe so they can roast instead of steam.

Roast to perfection:

Let everything cook for about twenty minutes, tossing halfway through, until the chicken is cooked through and those vegetables have started to caramelize at the edges.

The finishing touch:

Squeeze that fresh lime juice over the whole pan right when it comes out of the oven and sprinkle with cilantro if you are feeling fancy.

Save

These fajitas have become my go to for feeding a crowd because I can prep everything ahead and just pop the pan in the oven when guests arrive. Something about building your own fajitas at the table makes people linger longer and talk more, turning a simple dinner into a proper gathering.

Making It Your Own

I have swapped the chicken for skirt steak when I want something beefy and rich, or shrimp when I need something that cooks even faster. Portobello mushrooms work surprisingly well as a vegetarian option because they get meaty and savory in that high heat. You can even add sliced jalapeños to the pan if your household can handle the heat.

Serving Suggestions

While these fajitas are absolutely perfect on their own, I like to serve them with a pot of Mexican rice or some simple black beans seasoned with cumin and lime. A quick green salad with a citrus vinaigrette cuts through the richness and makes the whole meal feel a little more balanced.

Storage And Leftovers

The cooked chicken and vegetables keep beautifully in an airtight container for up to four days, and honestly they taste even better the next day when all those spices have had more time to mingle. I will sometimes make a double batch just to have fajita fillings ready for quick lunches throughout the week.

• Reheat leftovers in a skillet over medium heat to bring back some of those crispy edges
• The filling works amazing in scrambled eggs or breakfast burritos the next morning
• Wrap leftover filling in foil and freeze for up to three months for those emergency dinner nights

Save

There is something deeply satisfying about a meal that comes together this easily but still feels special enough for company. Hope these fajitas find their way into your regular rotation too.

Recipe FAQs

→ What is the best way to prepare the chicken for even cooking?

Cut the chicken breasts into thin, uniform strips to ensure they cook evenly and quickly when roasted on the sheet pan.

→ Can I use other vegetables besides bell peppers and onions?

Yes, you can add sliced mushrooms, zucchini, or jalapeños to introduce more variety and flavors to the dish.

→ How do I get the vegetables nicely caramelized?

Roast at a high temperature (425°F) and avoid overcrowding the pan so the steam doesn’t prevent caramelization.

→ What marinade spices enhance the dish's flavor?

A blend of chili powder, cumin, smoked paprika, garlic, onion powder, oregano, salt, and pepper adds warmth and depth.

→ How to serve this dish for a gluten-free option?

Use warm corn tortillas and avoid flour-based toppings or sides to keep it gluten-free.

→ Can this method be used for other proteins?

Absolutely—try sliced steak, shrimp, or portobello mushrooms for delicious variations using the same roasting technique.