Preheat the oven to 400°F (200°C). Spray a 9 x 13-inch casserole dish with nonstick cooking spray.
In a large bowl, combine the shredded chicken, sour cream, half of the shredded cheddar, 1 teaspoon ground cumin, 1/2 tablespoon chili powder, kosher salt, and 1/8 teaspoon black pepper; mix until evenly coated.
In a second bowl, combine the corn, drained black beans, the remaining 1 teaspoon cumin, remaining 1/2 tablespoon chili powder, and remaining 1/8 teaspoon black pepper; stir to combine.
Place two tortillas in the bottom of the prepared casserole dish, slightly overlapping if needed.
Spread half of the chicken mixture over the tortillas, then spread half of the bean and corn mixture over the chicken.
Top with the remaining two tortillas, then layer the remaining chicken mixture and the remaining bean mixture in the same order.
Sprinkle the remaining shredded cheddar evenly over the top.
Bake for 20 minutes, or until the cheese is melted and the casserole is heated through; if you prefer more browning, bake up to 30 minutes.
Remove from the oven and let rest a few minutes before slicing and serving hot.