Preheat your oven to 350°F (175°C).
In a mixing bowl, combine the shredded chicken, sour cream, chipotle sauce, cumin, garlic powder, salt, and pepper.
Layer the bottom of a baking dish with tortillas.
Spread half of the chicken mixture over the tortillas.
Sprinkle half of the black beans and corn over the chicken layer.
Add another layer of tortillas on top.
Spread the remaining chicken mixture over the second layer of tortillas.
Top with remaining black beans, corn, and half of the shredded cheese.
Finish with the last layer of tortillas and remaining cheese.
Cover with aluminum foil and bake for 25 minutes. Remove the foil and bake for another 15 minutes, or until the cheese is melted and bubbly.
Let the casserole cool for a few minutes before serving.