- unsalted butter for the baking dish, at room temperature
- 3 cups heavy cream
- ¼ cup prepared horseradish
- ¼ teaspoon ground nutmeg
- kosher salt and black pepper
- 3 pounds russet potatoes (about 6), peeled and thinly sliced
- Heat oven to 375° F. Butter a shallow 3-quart baking dish. In a large bowl, combine the cream, horseradish, nutmeg, 1½ teaspoons salt, and ¾ teaspoon pepper. Add the potatoes and toss to coat.
- Transfer the potato mixture to the prepared baking dish, pressing gently to submerge the potatoes. Cover the dish with foil, place on a rimmed baking sheet, and bake for 25 minutes. Remove the foil and bake until the potatoes are tender and the top is golden, 50 to 65 minutes.