Preheat the oven to 375°F (190°C) and lightly grease a 9x13-inch baking dish.
In a large bowl, combine the shredded chicken, black beans, corn, green chiles, cumin, chili powder, garlic powder, salt, and black pepper.
Spread a thin layer of enchilada sauce over the bottom of the baking dish.
Arrange one-third of the tortilla pieces in an even layer.
Spread half of the chicken mixture over the tortillas, drizzle with one-third of the enchilada sauce, and sprinkle with ¾ cup of the shredded cheese.
Repeat the layers with another third of the tortillas, the remaining chicken mixture, another third of the enchilada sauce, and ¾ cup of the cheese.
Top with the remaining tortilla pieces, pour over the remaining enchilada sauce, and finish with the remaining cheese.
Cover with foil and bake for 20 minutes.
Remove the foil and bake for another 10 to 15 minutes, or until the cheese is melted and bubbly.
Let the casserole rest for 10 minutes before garnishing with fresh cilantro and serving.