2 lb. Yukon Gold or russet potatoes, peeled
3 cups whipping or heavy cream (I used half and half)
1 tsp. kosher salt (mine needed much more salt)
1/8 tsp. freshly ground black pepper
Generous pinch of freshly grated nutmeg
2 cloves garlic, peeled and smashed
3/4 cup finely shredded Gruyère, Emmental, or Comté
Heat the oven to 400°F. Using a very sharp knife or a mandoline, carefully cut the potatoes into 1/8-inch slices (no thicker).
(Again, I would add chopped bacon and perhaps some thyme to give this dish some more flavor but the simplicity without these additions is delicious)
Put the potatoes in a large heavy-based saucepan and add the cream, salt, pepper, nutmeg, and garlic. Cook the mixture over medium-high heat until the cream is boiling, stirring occasionally (very gently with a rubber spatula so you don't break up the slices).
When the cream boils, pour the mixture into a 2-1/2- or 3-qt. baking dish. If you don't want a tender but garlicky surprise mouthful, remove and discard the garlic cloves. Shake the dish a bit to let the slices settle and then sprinkle the surface with the cheese.
Bake in the hot oven until the top is deep golden brown, the cream has thickened, and the potatoes are extremely tender when pierced with a knife, about 40 minutes. Don't worry if the dish looks too liquidy at this point; it will set up as it cools a bit. Before serving, let the potatoes cool until they're very warm but not hot (at least 15 minutes) or serve them at room temperature. (Note: I made mine a day ahead of time. The next day, I actually microwaved the dish, then finished it off under the broiler because of the timing of all of my other dishes. If you do this, I would add a bit extra cream before warming the dish in the microwave.)
