Preheat oven to 350 degrees Fahrenheit.
In a 9 x 13 glass baking dish, spread a little enchilada sauce, about 1/2 cup of gluten-free green enchilada sauce in the bottom of the casserole dish.
1 15 ounce can of your favorite green gluten-free enchilada sauce
On top of the sauce lay 6 gluten-free corn tortillas, overlapping so they fit the dish.
20 gluten-free corn tortillas
Spread 1 1/2 cups of cooked chicken that has been seasoned with taco seasoning, over the gluten-free tortillas.
3 cups cooked, shredded chicken
(If you don't have a premade mix of taco seasoning, it includes chili powder, onion powder, garlic powder, paprika, oregano, and salt.)
Sprinkle 1 cup of shredded cheese evenly on top of the chicken.
2 1/2 cups shredded cheddar cheese
Repeat steps 1-4 for another layer by first pouring half of the remaining green enchilada sauce over the chicken, followed by 6 more gluten free corn tortillas, 1 1/2 cups shredded chicken, and 1 cup of shredded Mexican style cheese.
Finally, top the entire casserole with 8 more GF corn tortillas.
Pour the rest of the GF enchilada sauce over the corn tortillas.
Top with the last 1/2 cup of shredded cheese.
Cover with aluminum foil so the top doesn't get crispy while the casserole cooks.
Bake for 30-35 minutes, or until cooked through.
Carefully remove from the hot oven and enjoy!