Russet potatoes will produce crisper crusts and fluffier centers. Yukon Golds will be slightly less crisp and have creamier centers, with a darker color and deeper flavor. You can also use a mix of the two.

The potatoes should be cut into very large chunks, at least 2 to 3 inches or so. For medium-sized Yukon Golds, this means cutting them in half crosswise, then splitting each half again to make quarters. For larger Yukon Golds or russets, you can cut the potatoes into chunky sixths or eighths.