Preheat oven to 400F and cover a baking sheet with parchment paper or a silipad.

Mandolin the potatoes into rounds roughly 1/8" thickness, or paper thin.

Toss potatoes with rosemary, sea salt, and olive oil.

Pile into 15-20 stacks, each roughly 1" high on the baking sheet. Place larger rounds on the bottom.

Bake for 40 minutes, or until crispy. 

Let cool and serve.