In-N-OutRaw Onions, Diced Grilled Onions, and Whole Grilled Onion SlicesRaw OnionsGrilled OnionGrilled OnionAsk for Grilled Onions or Whole Grilled Onions if you want to try something a little different than the traditional Raw Onion. You can mix and match any combination of these three options on a single burger!All Locations5 - Medium-HighFreehttp://hackthemenu.com/in-n-out/secret-menu/whole-grilled-onions/The In-N-Out secret menu allows more customization of the Onion preparation than one might think. The burgers come normally with a whole slice of raw onion. And most people know that you can get your onions grilled, and they come grilled to perfection and chopped up into little bits. But did you know that you can get a whole slice of grilled onion on your In-N-Out burger? Well you can! In fact, you can even get all three onion options on a single burger if you are crazy enough to try it! Be sure to check out the In-N-Out Secret Menu as well as visiting our home page to check out the complete list of All the Secret Menus from all your favorite restaurants!