2Toss chicken strips, peppers, and onions in a large bowl with olive oil, chili powder, cumin, paprika, garlic, salt, and pepper until everything is evenly coated.
3Spread mixture in a single layer on a sheet pan.
4Roast for 18–22 minutes, stirring once halfway through, until chicken is cooked through and peppers are tender with light char at the edges.
5Squeeze lime juice over the pan and toss to combine.
6Warm tortillas in a dry skillet or over a burner just before serving.
7Serve fajita filling with warm tortillas, sour cream, cilantro, and cheese on the side.