Preheat oven to 375 degrees F. Butter a 9-inch square baking/casserole pan.
In a large mixing bowl toss the chicken, rice, beans, corn and 3/4 cup of the cheese together.
Stir in all the sauce - it may seem like a lot but it will cook down. Season with salt and pepper to taste.
Spoon into the casserole pan and top with the chips. Sprinkle the rest of the cheese over top.
Bake 25 - 30 minutes until bubbly and golden on top.
Serve with a dollop of sour cream.