Instructions

1. 1
   Preheat the oven to 375°F (190°C).
2. 2
   Slice the peeled potatoes very thinly (about 1/8-inch thick) using a mandoline or a sharp chef's knife.
3. 3
   Do not rinse them; the starch helps thicken the cream.
4. 4
   Rub the inside of a shallow baking dish vigorously with the cut sides of the garlic clove, then grease the dish generously with one tablespoon of the butter . In a saucepan, combine the milk, heavy cream, salt, pepper , and ground nutmeg.
5. 5
   Bring to a bare simmer . Arrange one-third of the potato slices in overlapping layers along the bottom of the prepared dish.
6. 6
   Pour a third of the warm cream mixture over them and sprinkle with a third of the cheese.
7. 7
   Repeat the layers twice more, finishing with a generous layer of cheese and dotting the remaining butter across the top.
8. 8
   Bake in the preheated oven for 50 to 60 minutes, until the potatoes are tender when pierced with a knife and the top is a deep, bubbling golden brown.