2 pounds baking potato Russet or a Yukon Gold, peeled and thinly sliced
2 cups (50 cl) whole milk
3 cloves of garlic crushed and minced
3/4 teaspoon salt
3 bay leaves
Freshly ground nutmeg
Freshly ground black pepper
1 cup creme fraiche or heavy cream
2 cups freshly grated Gruyere cheese
Preheat oven to 375 degrees F
Place the sliced potatoes in a large saucepan and cover with the milk and 2 cups of water. Add the garlic, salt, and bay leaves. Bring to a boil over medium-high heat, stirring occasionally so that the potatoes do not stick. Reduce the heat to medium and cook, stirring from time to time, until the potatoes are tender but not falling apart, about 10 minutes.
Using a slotted spoon, transfer half of the potatoes to a large, 14- by 9- by 2-inch buttered baking dish. Sprinkle with the nutmeg, pepper, half the creme fraiche, and half the cheese. Cover with the remaining potatoes, and sprinkle again with nutmeg, pepper, and the remaining creme fraiche and cheese.
Bake, uncovered, until the gratin is crisp and golden on top, about 1 hour. Serve immediately.