It sounds like a bar mishap—a shot of amaretto dropped into a frosted mug of Coors Light and orange juice. And indeed, Tammy Lucas, who inherited the funky neighborhood Edna’s Club & Restaurant in Oklahoma City from her mother, Edna Scott, says the creation may have been unintentional. Scott was probably making a Boilermaker and added orange juice by mistake. However it happened, the Lunchbox has become a phenomenon—a clicker on the Edna’s website passed two million served more than a year ago. Edna’s has added variations, including the Great Balls of Fire Box, made with Fireball cinnamon whiskey. The inspiration: For years, Edna would dance atop the bar when anyone played “Great Balls of Fire” on the jukebox.