01 - Preheat oven to 375°F and lightly grease a 9x13-inch baking dish.
02 - Combine shredded chicken, 1 cup enchilada sauce, 1 cup cheese, sour cream, corn, onion, green chiles, cumin, garlic powder, smoked paprika, salt, and pepper in a large bowl. Mix until thoroughly combined.
03 - Spread 1/2 cup enchilada sauce across the bottom of the prepared baking dish.
04 - Arrange 4 corn tortillas in the dish, slightly overlapping to cover the sauce base.
05 - Spread half of the chicken mixture evenly over the tortillas.
06 - Drizzle 1/2 cup enchilada sauce over the chicken, then sprinkle with 1/2 cup cheese.
07 - Repeat with 4 tortillas, remaining chicken mixture, 1/2 cup enchilada sauce, and 1/2 cup cheese.
08 - Top with remaining 4 tortillas, remaining enchilada sauce, and final 1/2 cup cheese.
09 - Cover with foil and bake for 25 minutes.
10 - Remove foil and bake 10 additional minutes until cheese is bubbly and casserole is heated through.
11 - Let casserole rest for 10 minutes before slicing. Garnish with cilantro, jalapeños, and additional sour cream if desired.