Doritoos Cheesy Chicken Casserole

3 cups cooked chicken (shredded) 8 oz sour cream 1 can cream of mushroom soup 1 can cream of chicken soup 1 can of corn, drained 2 cups Cheddar cheese, shredded 1/2 to 1 bag of nacho cheese Doritos Preheat oven to 350 degrees. Lightly spray a 9x13 pan with cooking spray.  Crush the entire bag of Doritos and cover the bottom of the dish.  Reserve one cup of cheese.   Mix together remaining ingredients in a large bow.  Pour chicken mixture over the Doritos.  Bake for 20 min. Top casserole with the remaining cheese and bake 5 additional minutes or until melted.