Ingredients
2 pounds sweet potatoes
1 disk Test-Kitchen Piecrust
All-purpose flour, for surface
2 large eggs, lightly beaten
1/2 cup whole milk
1/2 cup heavy cream
1/3 cup granulated sugar
1/4 cup light-brown sugar
1/2 teaspoon salt
1/2 teaspoon freshly grated nutmeg
1 teaspoon pure vanilla extract
3 large egg whites
Pinch of salt
1/4 teaspoon cream of tartar
1/2 cup granulated sugar
Preparation
Sweet-Potato Pie: Preheat oven to 425°F. Pierce sweet potatoes in a few places with a fork, and bake until very soft, about 1 hour 15 minutes, depending on size of potatoes.
Meanwhile, roll out dough into a 12-inch round on a lightly floured surface. Fit into a 9-inch pie plate, and trim edge, leaving a 1/2-inch overhang. Refrigerate until firm, about 1 hour.
When sweet potatoes are cool enough to handle, scoop out enough flesh to measure 2 cups (reserve any remaining flesh for another use), and transfer to a food processor. Add eggs, milk, cream, sugars, salt, nutmeg, and vanilla, and process until smooth.
Reduce oven temperature to 375°F. Pour filling into crust. Bake until filling puffs and cracks around edge and pie is just set, 50 to 55 minutes. Let cool completely on a wire rack, about 2 1/2 hours. Pie can be kept at room temperature for 1 day, covered loosely with parchment or foil.
Meringue: Beat egg whites, salt, and cream of tartar in a bowl with a mixer on low speed until foamy. Raise speed to high, and add granulated sugar in a slow, steady stream. Whisk until stiff, glossy peaks form, about 5 minutes. Spoon meringue on top of pie. Lightly brown meringue in places with a small kitchen torch (or broil about 7 inches from heat source about 45 seconds).
