In-N-Out's Iconic 'Animal Style' Burger Originated from a 1960s Customer Request
In-N-Out Burger's famous 'Animal Style' order originated in the early 1960s when a customer requested a customized burger prepared by an employee. The chain, founded in 1948 in Los Angeles, has kept this and other off-menu items as an 'open secret' for decades, eventually listing them on a 'Not-So-Secret Menu' in 2005. The burger features a mustard-cooked patty, pickles, extra spread, and grilled onions, and remains a popular order despite being absent from the standard menu.