A cheeseburger is a hamburger topped with
cheese. Traditionally, the slice of
cheese is placed on top of the meat patty, but the burger can include many variations in structure, ingredients, and composition. The
cheese is normally added to the cooking hamburger patty shortly before the patty is entirely cooked, which allows the cheese to melt. As with other hamburgers, a cheeseburger may include toppings, such as lettuce, tomato, onion, pickles, mustard, mayonnaise, ketchup, or bacon.