How to Make Hamburger Boats
- Mix beef, bread crumbs, egg, salt, and pepper in a bowl.
- Shape into tiny meat balls and brown lightly in a skillet.
- Add onion, tomato sauce, and water; cover and simmer gently for 20 minutes, stirring occasionally.
- Add mushrooms and simmer 10 minutes more. Hollow out rolls and fill with meatballs and sauce.