Preheat your oven to 425°F (220°C). Line your sheet pan with parchment paper or a light coat of olive oil to prevent sticking and make cleanup easier.
Slice the red and green bell peppers into thin strips. Peel and slice the yellow onion into similar-sized strips. Cut the chicken breasts into even strips, about 1-inch wide, to ensure they cook evenly alongside the vegetables.
In a large mixing bowl, combine the olive oil, chili powder, cumin, garlic powder, onion powder, salt, and pepper. Toss the chicken strips in this mixture until they’re thoroughly coated. Add the sliced peppers and onions to the bowl and toss again to coat everything evenly.
Spread the chicken, peppers, and onions out in a single layer on your prepared sheet pan. Make sure there’s some space between the pieces so they roast properly and don’t steam.
Place the sheet pan in the preheated oven and roast for 20 to 25 minutes. About halfway through cooking, use tongs to flip the chicken and stir the vegetables to promote even browning and caramelization.
Once the chicken is cooked through and the vegetables are tender with charred edges, remove the sheet pan from the oven. Sprinkle chopped fresh cilantro over the top and serve with lime wedges for squeezing over each portion.
