Preheat your oven to 350°F (175°C).
In a large mixing bowl, combine the shredded chicken, black beans, corn, onion, garlic powder, cumin, salt, and pepper.
Pour half of the enchilada sauce into the bottom of a 9x13 inch baking dish.
Layer 4 corn tortillas over the sauce, slightly overlapping them.
Spread half of the chicken mixture evenly over the tortillas.
Sprinkle 1 cup of shredded cheese on top of the chicken layer.
Repeat the layers with the remaining tortillas, chicken mixture, and finish with the rest of the enchilada sauce.
Top with the remaining cheese.
Cover the dish with aluminum foil and bake for 20 minutes.
Remove the foil and bake for an additional 10 minutes, or until the cheese is bubbly and golden.