Preheat the oven to 425°F. In a 9x13 inch oven safe casserole dish, pour 1 cup of the enchilada sauce down in an even layer. Then, place a layer of tortillas over this. Cut the tortillas in half so they fit nicely in the pan without any gaps. (See video for guidance).
1 (28 oz.) can Green enchilada sauce, 9, 8-inch flour tortillas (corn tortillas work too)
In a medium sized bowl, mix 1 cup of sour cream and 1 cup of the enchilada sauce together. Set aside.
1 cup sour cream, 1 (28 oz.) can Green enchilada sauce
In a large bowl, make the chicken mixture. Combine the shredded chicken, diced green chiles, pinto beans, 6 oz. shredded cheese, diced jalapeño (optional) and garlic powder.
1 Rotisserie chicken, shredded, 1 (4 oz.) can Diced green chiles, 1 (15. oz.) can Pinto beans*, drained and rinsed, 8 oz. Mexican Style Four Cheese Blend (shredded), divided, 1 jalapeño, diced, 1 tsp. garlic powder
Next, layer 1 cup of the sour cream/enchilada sauce mixture on top of the tortillas followed by 2 cups of the chicken mixture. Then continue to layer: tortillas, sauce and chicken mixture, tortillas.
Finish the casserole with one last layer of tortillas (you will have 9 tortillas total in the casserole) a little more sauce and a heavy sprinkle of cheese. Loosely cover with foil. Bake for 20 minutes with the foil on and 10 minutes with the foil off. (In those last 10 minutes you can also broil on high for 3-5 minutes to get a nice brown color on top, be sure to watch it so it doesn't burn!)
Allow to cool, then slice and garnish with your favorite toppings (sour cream, green onions, tomatoes, hot sauce, avocado, etc.).