1Heat oven to 350. spray a 2-quart casserole dish w/ cooking spray. Spray a lg skillet w/ cooking spray. In bowl, combine chicken, garlic and chili powder, mix to combine.
2Add chicken mix to skillet, over med-high heat. Cook, stirring, for 6 mins. Remove chicken. Add oil to skillet. Add onion and peppers to skillet. Cook, stirring for 5 mins. Stir in spinach.
3Spread 1/2 cup salsa in bottom of casserole dish. Top w/ 1/2 tortilla pieces, 1/2 chicken mix and 1/2 veggie mix. Pour remaining salsa over veggies. Sprinkle w/ some cheese. Repeat layers, except cheese. Bake, covered for 30 mins. Sprinkle w/ remaining cheese. Garnish w/ tomatoes and advocado.