Heat the oven to 350°F
Beat the soup, milk and eggs in a medium bowl with a fork or whisk
Stir in the corn, corn muffin mix, cheese, and ½ cup onions
Pour the soup mixture into a 9-inch cast iron skillet or 1 ½-quart casserole
Bake for 30 minutes or until the mixture is hot
Top with the remaining ½ cup onions
Bake for 5 minutes or until the onions are golden brown
