Preheat oven to 350 degrees. In a large mixing bowl blend together sour cream, 1 cup salsa, green chiles, cilantro, chili powder, paprika, cumin, onion powder, and season with salt and pepper to taste. Fold in shredded chicken.
Spray an 11 by 7-inch baking dish with cooking spray and spread 1/3 cup salsa evenly in bottom of dish.
Layer 15 tortilla quarters evenly over salsa, slightly overlapping each other (the flat cut sides of tortillas should be facing the rim of dish and rounded sides facing inward).
Spread 1/2 of the chicken mixture evenly over tortilla layer the sprinkle 1/2 cup corn evenly over chicken mixture layer.
Spread 1/2 cup Monterey Jack and 1/2 cup Cheddar evenly over corn layer, the repeat this process once more (tortillas (you'll have 2 quarters left over), chicken mixture, corn, cheeses.
Tent with foil and bake in preheated oven 40 minutes, then remove foil and bake 20 minutes longer.
Remove from oven and allow to rest 5 minutes then cut and serve with fresh tomatoes, avocados (or guacamole), additional sour cream, fresh cilantro, lime juice and hot sauce as desired.
*I cooked the chicken in chicken broth in the slow cooker, rotisserie chicken will work great too.**Don't use flour tortillas, corn is a must for this. Also look for some that are fairly stiff and sturdy, not delicate and flimsy.