Generously butter 9 x 13 inch baking dish. Arrange bread cubes in dish and sprinkle with cheese. Beat together next 5 ingredients with pepper to taste and pour evenly over cheese and bread. Sprinkle with bacon, mushrooms and tomato. Cover and chill overnight.

Preheat oven to 325 F. Bake casserole uncovered until set, about 1 hour (tent with foil if top begins to over brown.) Serves 12.