How to Make It
Heat oven to 350° F with the rack in the lowest position. Roll the dough into a 12-inch circle on a floured work surface. Transfer to a 9-inch pie plate. Trim the dough to a 1-inch overhang and tuck under itself to form a thick rim; crimp the edge. Chill for at least 30 minutes.
Combine the sweet potato puree, flour, sugar, cream, eggs, butter, vanilla, nutmeg, and salt in a large bowl. Pour the mixture into the chilled piecrust and bake until the center is set but still slightly wobbly, 50 to 55 minutes. Let cool.
Serve with the whipped cream.