The Egg McMuffin, introduced in 1972, became McDonald’s signature breakfast sandwich.
Herb Peterson, a McDonald’s franchisee in Santa Barbara, California, developed the sandwich with his assistant, Donald Greadel. Its English muffin, egg, Canadian bacon, and cheese were designed as a portable version of an eggs Benedict-style meal.
The product helped establish breakfast as a major part of McDonald’s brand identity. It was first tested in 1971 and expanded to McDonald’s restaurants in 1972. Its “Mc” naming linked the new breakfast item to the company’s established product family.
The Egg McMuffin is commonly confused with later breakfast products such as the McGriddle and the Big Breakfast. Those items came later; the Egg McMuffin was the early sandwich that helped define McDonald’s morning menu.