Preheat your oven to 425°F (220°C) and prepare a large baking sheet by lining it with parchment paper.
In a spacious mixing bowl, combine the thinly sliced chicken, red and green bell peppers, and onion strips.
Drizzle the olive oil over the chicken and vegetables, then add the fajita seasoning, garlic powder, smoked paprika, ground cumin, and a sprinkle of salt and freshly cracked pepper.
Using your hands or two large spoons, gently toss everything together until the chicken and vegetables are thoroughly coated with oil and seasonings.
Spread the seasoned chicken and vegetable mixture onto the prepared baking sheet in a single, even layer.
Place the baking sheet in the preheated oven and bake for 20-25 minutes, stirring halfway through.
Once the chicken is fully cooked and registers an internal temperature of 165°F (74°C), remove the baking sheet from the oven and let it cool for a couple of minutes.
Transfer the sizzling fajita mixture to a platter for serving, garnish with freshly chopped cilantro, and arrange lime wedges on the side.
Allow everyone to serve themselves by filling their warm tortillas with the chicken and vegetable mix and squeezing fresh lime juice over the filling.
Notes
Serve with colorful side dishes like guacamole and salsa for a vibrant meal.