In a large bowl, combine the ground beef, egg, garlic powder, onion powder, bread crumbs, salt and black pepper. (I like to use a fork for this. It gets everything blended without overworking the mixture.) Scoop about 1/4 cup of the meat mixture and roll it into a ball. Place the meatball into the slow cooker on top of the sauce and repeat until all of the meat mixture has been formed into balls. Top with the other jar of sauce and cook covered on low for about 5 hours.