Line a 12" Dutch Oven with heavy-duty foil. Lightly grease the foil with butter. Break up bread into the oven. Crumble cooked sausage meat over bread and cover with cheese. In a separate bowl, mix eggs (lightly beaten), milk, dry mustard, and 1 tsp. salt (to taste). Pour the egg mixture over the layered bread/sausage/cheese in the oven, cover, and bake for 35 - 40 minutes, checking occasionally. The cheese rises to the top, melting into a golden brown crust over a fluffy layer of eggs, making a super filling camp breakfast for a crowd!