1Break buttered bread into pieces and put in the bottom of a greased 9- by 13-inch pan.
2Spread grated cheese over bread.
3Add any extra goodies you choose and sprinkle over the cheese.
4Pour combined milk, beaten eggs, salt and dry mustard over all.
5Refrigerate AT LEAST over night; longer is okay.
6Bake at 350 degrees for 1 hour. I usually leave the casserole covered with aluminum foil for the first 30 minutes and then remove the foil for the last 30 minutes of baking. The casserole is done when it is bubbling and lightly browned.