Prep the chicken and veggies. Slice the chicken into thin strips. Cut peppers and onion into 1/4-inch slices so they cook quickly and evenly.

Make the spice blend. In a small bowl, mix chili powder, cumin, smoked paprika, oregano, a pinch of salt, black pepper, and optional cayenne. This is your fajita seasoning.

Marinate the chicken. In a large bowl, toss chicken with 1.5 tablespoons olive oil, the minced garlic, half the spice blend, lime zest, and half the lime juice. Let it sit 10–20 minutes while you heat the pan and prep toppings.

Heat the pan. Use a large cast-iron or heavy skillet over medium-high heat. Add 1 tablespoon olive oil and let it get hot until shimmering.

Cook the peppers and onion. Add peppers and onion with a big pinch of salt and the remaining spice blend. Cook 5–7 minutes, stirring occasionally, until lightly charred at the edges but still crisp. Transfer to a plate.

Sear the chicken. Add the remaining 0.5 tablespoon oil to the hot pan. Spread chicken in a single layer. Cook 4–6 minutes, flipping once, until cooked through with caramelized edges.

Combine and finish. Return peppers and onions to the pan. Toss with the remaining lime juice and chopped cilantro. Taste and adjust salt, pepper, or lime as needed.

Warm the tortillas. Heat tortillas in a dry skillet for 20–30 seconds per side or wrap in foil and warm in a low oven. Keep them covered so they stay soft.

Serve. Pile fajita mix into warm tortillas. Add your favorite toppings. Serve extra lime wedges on the side for brightness.