Preheat your oven to 375°F (190°C).
In a large bowl, mix the shredded chicken, black beans, corn, diced tomatoes, salsa, chili powder, cumin, salt, and pepper.
Lightly grease a 9x13-inch baking dish.
Layer half of the chopped tortillas on the bottom of the dish.
Top with half of the chicken mixture and sprinkle with half of the cheese.
Repeat the layers with remaining tortillas, chicken mixture, and cheese.
Cover with foil and bake for 25 minutes. Remove foil and bake an additional 10 minutes or until cheese is melted and bubbly.
Garnish with fresh cilantro and green onions, if desired. Serve warm.