Gratin di Patate alla Fontina (Italian Potato Gratin) A gratin is judged on a cut face. Lift out the first portion and you should see distinct layers of potato held by a set custard of milk, cream and melted Fontina, with a dark blistered crust on top and no loose liquid running into the gap. Nothing about that is accidental. It comes from the thickness of the slice, from cooking the potatoes in the dairy first, and from the rest that almost everyone skips. Fontina DOP is wha