I tried this once and really liked it. Watch out with the milk - if you put too much, the potatoes will be too watery, but you have to put enough to make them soft and tasty.
Serves 6
2 1/4 pounds potatoes
3 2/3 cups milk
pinch of ground nutmeg
1 bay leaf
1-2 tbsp butter, softened
2-3 garlic cloves, very finely chopped
3-4 tbsp creme fraiche or heavy cream
salt and fresh ground black pepper
1) Preheat the oven to 350 degrees F. Cut the potatoes into fairly thin slices.
2) Put the potatoes in a large saucepan and pour over the milk, adding more to cover if needed. Add the salt and pepper, nutmeg and the bay leaf. Bring slowly to a boil over medium heat and simmer for about 15 minutes until the potatoes just start to soften, but are not completely cooked, and the milk had thickened.
3) Generously butter a 14 inch oval gratin dish or an 8 cup shallow baking dish and sprinkle the garlic over the base.
4) Using a slotted spoon, transfer the potatoes to the gratin or baking dish. Taste the milk and adjust the seasoning, then pour over enough of the milk to come just to the surface of the potatoes, but not cover them. Spoon a thin layer of cream over the top or add more of the thickened milk to cover.
5) Bake the potatoes for about 1 hour until the milk is absorbed and the top is a deep golden brown.
Source: French - Delicious Cuisine Made Easy by Carole Clements and Elizabeth Wolf-Cohen