Tightly cover the unbaked casserole and refrigerate no longer than 24 hours. About 1 1/4 hours before serving, heat your oven to 325°F. Uncover and bake 50 minutes. Sprinkle with 1/4 cup Cheddar cheese; bake 10 to 15 minutes longer or until the center is hot.
If you don't have a quiche dish, you can use a 9-inch pie plate.