The McDonald’s sandwich famous for two beef patties and special sauce is the Big Mac.
McDonald’s introduced the Big Mac in 1967. It was created by franchisee Jim Delligatti, who operated restaurants in the Pittsburgh area. The sandwich used two beef patties, a middle bun layer, lettuce, cheese, pickles, onions, and the sauce that became central to its identity.
Its three-part bun and stacked presentation made the Big Mac visually distinctive in McDonald’s advertising. The product became one of the company’s signature branded items and later gave its name to the Big Mac Index, an informal comparison of international currency values.
The Big Mac is sometimes confused with the Quarter Pounder because both are flagship hamburgers. The defining structural feature here is the Big Mac’s two patties separated by a middle bun layer.