01 - Preheat your oven to 375°F. Lightly grease a 9x13 inch baking dish with cooking spray or a small amount of oil.
02 - In a large bowl, combine shredded chicken, 1 cup enchilada sauce, black beans, corn, red onion, cumin, chili powder, garlic powder, salt, and pepper. Mix until all ingredients are evenly distributed throughout the chicken.
03 - Spread 1/2 cup of enchilada sauce evenly across the bottom of the prepared baking dish to prevent sticking and add flavor to the base.
04 - Arrange four tortillas over the sauce, tearing them as needed to fit and cover the entire bottom of the dish.
05 - Spread half of the chicken mixture evenly over the tortillas. Sprinkle with 2/3 cup of shredded Mexican cheese blend.
06 - Add another layer of tortillas over the cheese. Top with the remaining chicken mixture and sprinkle with another 2/3 cup of cheese.
07 - Place the final layer of tortillas over the filling. Pour the remaining 1/2 cup enchilada sauce evenly over the surface. Top with the remaining cheese and sliced black olives if desired.
08 - Cover the baking dish tightly with aluminum foil. Bake for 20 minutes to allow the flavors to meld and the casserole to heat through.
09 - Remove the foil and bake uncovered for an additional 10 minutes, or until the cheese is bubbly and lightly golden brown on top.
10 - Let the enchilada bake rest for 5 minutes before serving. Garnish with fresh cilantro, green onions, sliced avocado, and serve with sour cream and lime wedges on the side.