Preheat oven to 350°F
Grease a 9 x 13 inch baking pan.
In a large bowl, mix all ingredients together and spread it out in a casserole dish.
Bake for 45 minutes or until brown on top and cheese has melted.
In the last few minutes of baking, sprinkle the top of the casserole with additional cheese and bake until melted. Serve.
* optional - Sprinkle with sliced green onions