Big Mac in box container

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When the Big Mac joined McDonald's menus in the 1960s, it was an instant hit, changing everything when McDonald's introduced it. With its special sauce and distinctive three-layer sesame seed bun, the Big Mac not only has a flavor that stands out in the fast food landscape but also a unique profile as well. Fans and critics alike may wonder, what purpose does the middle bun serve? And how did it get there?

Each part of the Big Mac bun has a specific name, the crown (top), club (middle), and heel (bottom). At the time of its invention, McDonald's didn't offer a double hamburger like it does now. The Big Mac's creator, Micheal James "Jim" Delligatti, wasn't satisfied with how two meat patties plus toppings fit on the standard McDonald's burger bun. Delligatti ordered special sesame seed buns from a local bakery and sliced them into three pieces. The addition of the club layer gave his new burger more stability. Nowadays, customers can take advantage of that sturdy structure to score an even bigger Big Mac by sizing up the meat patties. 

Where did the middle bun come from?

Jim Delligatti didn't come up with the Big Mac's triple layer bun all on his own. By his own admission, he was inspired by another iconic burger that had been on the market since the 1930s: the Double-Deck Hamburger, known today as the Big Boy. The invention of the double burger is just one of many little-known truths about Big Boy restaurants.

According to legend, Big Boy founder Bob Wian was inspired to create the double-deck burger with its three slices of bun when a regular customer asked him one night for something different from the usual burger. Wian may have been riffing on a club sandwich, which is made with three slices of toasted bread in order to give the layered sandwich a sturdier structure. The earliest mention of a club sandwich was made in an 1889 issue of The Evening World newspaper, so Wian was likely aware of the sandwich in the 1930s. It seems probable McDonald's also made this connection given that it calls the middle layer of its Big Mac bun the club.