In-N-Out does $2 billion in annual sales. It breaks one rule other fast-food chains follow

An off-menu item is one of In-N-Out’s biggest selling points. Since its inception, the West Coast burger chain has built its reputation on a stripped-down menu of burgers, fries, and shakes. In 2005, the chain began listing some of its most popular off-menu orders publicly under the “Not-So-Secre