Egg and Sausage Breakfast Casserole

8 slices bread (square sandwich bread)
2 c. shredded american cheese
2-1/2 c. milk
3/4 tsp dry mustard
1-1/2 pound sausage
4 eggs
1 can cream of mushroom soup
1/2 c. milk

Cook sausage and drain well. Cut break slices in 4 to 6 pieces and place in buttered baking 9 x 13 baking dish. Top with sausage and cheese. Let stand overnight refrigerated. The next morning, or not long before baking, dilute soup with 1/2 c. milk. Pour over above and bake at 300 degrees for 1-1/2 hours, setting in a pan of hot water. (An oblong boiler pan works well.) Serves 12 to 16.