Pull apart bread into small, dime-size pieces. Combine ground beef, bread, salt, pepper, and minced onion in a large mixing bowl. Using a spoon, scoop out rounds of meat mixture, or shape into several round, 5 cm balls by hand. Brown meatballs in a hot skillet using a small amount of butter or oil. Turn them occasionally so all sides are browned. Place meatballs in a crockpot. Add soup and water. Cook on Low for 6-12 hours, or High for up to 6 hours.