Preparation Preheat oven to 350°F with rack in upper third. Generously butter a 2 1/2-quart shallow baking dish (not glass). Stir together nutmeg, 2 teaspoons salt, and 3/4 teaspoon pepper. Peel and thinly slice potatoes. Layer potatoes in baking dish, overlapping slightly and sprinkling each layer with some of salt mixture and some of butter. Pour cream and milk over potatoes, pressing down gently to submerge potatoes in liquid. Cover with foil and bake until potatoes are tender, 1 to 1 1/4 hours. Remove gratin from oven and discard foil. Turn broiler on and broil gratin 2 to 3 inches from heat until top is browned in spots, 3 to 5 minutes. Let stand 10 minutes before serving. Cooks' note:Potatoes are best the day they're made but can be baked and broiled 2 days ahead and chilled, uncovered, until cool, then covered. Reheat, covered, in a 350°F oven about 40 minutes.
Preparation Preheat oven to 350°F with rack in upper third. Generously butter a 2 1/2-quart shallow baking dish (not glass). Stir together nutmeg, 2 teaspoons salt, and 3/4 teaspoon pepper. Peel and thinly slice potatoes. Layer potatoes in baking dish, overlapping slightly and sprinkling each layer with some of salt mixture and some of butter. Pour cream and milk over potatoes, pressing down gently to submerge potatoes in liquid. Cover with foil and bake until potatoes are tender, 1 to 1 1/4 hours. Remove gratin from oven and discard foil. Turn broiler on and broil gratin 2 to 3 inches from heat until top is browned in spots, 3 to 5 minutes. Let stand 10 minutes before serving. Cooks' note:Potatoes are best the day they're made but can be baked and broiled 2 days ahead and chilled, uncovered, until cool, then covered. Reheat, covered, in a 350°F oven about 40 minutes.