These Salisbury Steak Meatballs are a delicious twist on classic Salisbury steak, made with lean ground beef mixed with breadcrumbs, egg, and seasonings, then pan-fried until golden. They are simmered in a rich, savory onion gravy made from butter, onions, flour, beef broth, and Worcestershire sauce, making them a hearty and comforting meal perfect for any occasion.