1 lb. hamburger
1/4 c. onion, chopped
1/2 c. grated cheese
Add salt & pepper to taste
1 can mushroom soup
1 egg, beaten
1/2 c. bread crumbs

Mix ingredients well. Trim crust from 16 to 18 buttered bread slices. Put bread slices butter side down into muffin cups. Fill with meat mixture. Bake at 350 degrees for 40 minutes.