Use whatever proportion of milk and half-and-half suits you, depending on the richness you desire in the final product. We suggest starting with 2 cups half-and-half to 1 cup milk.
Preheat the oven to 350┬░F. Rub a 12-inch gratin dish or a shallow 3-quart baking dish with:
1 clove garlic, halved
Let dry, then coat with:
1 tablespoon butter, softened
Combine in a large saucepan or Dutch oven:
2 1/2 pounds baking potatoes, peeled and very thinly sliced
3 cups milk or half-and-half or a combination
1 teaspoon salt
1/4 teaspoon ground black pepper
Pinch of freshly grated nutmeg or ground nutmeg
Bring the mixture to a gentle boil over medium heat, then cook and stir until the liquid thickens slightly, about 5 minutes. Pour the mixture into the prepared dish. Press down on the top layer to submerge the potatoes. Sprinkle with:
1 cup Grated Gruyère cheese or Fontinella cheese
Bake until the top is golden and the potatoes are tender, 45 minutes to 1 hour.
