Preheat oven to 375°F (190°C). Lightly grease a 9x13-inch baking dish.
In a large bowl, mix the enchilada sauce, cream of chicken soup, and sour cream until smooth.
Stir in garlic powder, onion powder, salt, and pepper.
Layer 1/3 of the tortilla pieces on the bottom of the baking dish.
Top with 1/3 of the shredded chicken, sauce mixture, and cheeses.
Repeat layers two more times, ending with cheese on top.
Cover with foil and bake for 25 minutes. Remove foil and bake another 10 minutes, until bubbly and golden.
Let sit for 5-10 minutes before serving. Garnish with chopped cilantro if desired.