Preheat oven to 350. In small bowl combine oil, chili powder, cumin, chili flakes, garlic, salt and pepper. Toss chicken, veggies and oil mixture together on a large sheet pan with one inch edge. Spread out evenly.
Bake for 25-30 minutes until chicken is cooked and the veggies are soft with a crispy edge. Sprinkle with cheese, place back in oven until melted, then serve.
Serve with sour cream, avocado and all your favorite fajita fixins! Just make sure to log your extras.