Potato Gratin Recipe
- 1 cup milk
- 1 cup heavy cream
- 2 cups finely sliced leeks, white part only
- 1 tablespoon roasted garlic purée (see note)
- 1 tablespoon chopped rosemary leaves
- Pinch freshly ground nutmeg
- Coarse salt and freshly ground white pepper to taste
- 5 tablespoons unsalted butter, at room temperature
- 4 large Yukon Gold potatoes, peeled and cut, crosswise, into 1/8-inch-thick slices
- Preheat the oven to 400°F.
- Combine the milk and cream with the leeks, garlic purée, rosemary, and nutmeg in a large heavy saucepan over medium heat. Add salt and white pepper and bring to a simmer. Whisk in 3 tablespoons of the butter, remove from the pan from the heat, and keep warm.
- Using the remaining butter, generously coat the interior of an 11-by-7-by-2- inch baking pan. Set aside.
- Season the potatoes with salt and pepper. Using about half of the potatoes, cover the bottom of the prepared pan with a layer of slightly overlapping potato slices. Pour half of the milk mixture over the potatoes. Make another layer with the remaining potatoes and cover it with the remaining milk mixture.
- Bake for about 1 hour, or until the tip of a small, sharp knife is easily inserted into the center.
- Remove from the heat and use as a side dish with meat, game, or poultry.
