Meatball sandwich is an Italian-American invention typically consisting of a long Italian-style roll filled with meatballs, red sauce, and mild cheeses such as mozzarella or provolone. It is believed that this sandwich was invented in the USA at the turn of the 20th century.
Nowadays, there are numerous variations on the meatball sandwich, but the meatballs are usually made with a combination of ground pork and beef, enriched with eggs, bread crumbs, garlic, basil, parsley, and onions. For the best experience, this sandwich should be followed by a glass of cold beer.