Melt the butter in a
cast iron or
stainless steel skillet and scramble the eggs. Layer eggs, peppers, mushrooms, bacon, and onions in a 9x13
baking dish. Warm soup with milk in a medium saucepan over medium heat, then pour over the top. Spread cheese all over the top, cover with foil, and refrigerate overnight. Uncover and bake at 350* for 50 minutes.