Peeling the potatoes is an opinionated matter and one of the most debatable questions in Au Gratin Potato history. Many people believe peeling them will make for a more crispy potato crust, but others say you should leave them unpeeled to avoid wasting nutrients. Whatever your choice is for peeling potatoes, make sure to use Russet Potatoes for best results! White potatoes will not have a lot of flavors when cooked this way.