They have a "secret menu". Google In-N-Out burger secret menu. Yes they are AMAZING!!!
Quick guide for the secret menu for those that found this and cba to look it up: [Number] by [number2]: amount of patties and cheese. Ex: 3 by 3 for 3 patties and 3 cheese slices. Etc. Animal Style: carmelized onions and thousand island dressing (you can order fries like this as well as burgers and they're great) Low-carb Style: swap buns for lettuce wrapped around everything Neapolitan shake: exactly what it sounds like: all three shake flavors combined. There are a couple other crazy options, but those are the basics.
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