#1. Heat oven to 400°F. Spray 13x9-inch (3-quart) glass baking dish with cooking spray. Cut onion and bell pepper into even slices place in baking dish. #2. Cut chicken breasts into thin strips add to vegetables in dish. Sprinkle with seasoning mix drizzle with oil. Stir until combined and pieces are coated. #3. Bake 35 to 40 minutes, stirring once halfway through baking, until chicken is no longer pink in center. #4. Spoon small amount of chicken and veggies onto each tortilla. Top each with sour cream, salsa and cilantro, or your favorite fajita toppings.