Melt 1 tablespoon fat in a large frypan. Add Onion and green pepper. Cook until tender. Mix eggs, milk, salt, and pepper. Pour over Onion and green pepper. Cook over low heat, stirring occasionally to let uncooked portion flow beneath cooked portion. Continue cooking until eggs are set but still moist. Divide into 6 portions. Spread toasted muffin halves with 1 tablespoon butter or margarine. Top muffin halves with egg mixture and a slice of Cheese. Broil until Cheese is melted and lightly browned, about 5 minutes. Note: for this recipe, use only clean eggs with no cracks in shells. [karen adds: because of the risk of salmonella poisoning, it"s been widely recommended that children, the elderly, and immuno-compromised persons avoid consuming any raw or undercooked eggs.] calories per sandw