Roll dough into 12-inch circle on floured counter. Loosely roll dough around rolling pin and gently unroll it onto 9-inch pie plate, letting excess dough hang over edge. Ease dough into plate by gently lifting edge of dough with your hand while pressing into plate bottom with your other hand.

Trim overhang to ½ inch beyond lip of plate. Tuck overhang under itself; folded edge should be flush with edge of plate. Crimp dough evenly around edge of plate. Wrap dough-lined plate loosely in plastic wrap and refrigerate until firm, about 30 minutes. Adjust oven rack to middle position and heat oven to 350 degrees.

Line chilled pie shell with double layer of aluminum foil, covering edges to prevent burning, and fill with pie weights. Bake on foil-lined rimmed baking sheet until edges are set and just beginning to turn golden, 25 to 30 minutes, rotating sheet halfway through baking.

Remove foil and weights, rotate sheet, and continue to bake crust until golden brown and crisp, 10 to 15 minutes longer. Transfer sheet to wire rack. (Crust must still be warm when filling is added.) Increase oven temperature to 400 degrees.

While crust is baking, whisk cream, milk, eggs and yolks, and vanilla together in bowl; set aside. Bring pumpkin, sweet potatoes, sugar, maple syrup, ginger, salt, cinnamon, and nutmeg to simmer in large saucepan over medium heat and cook, stirring constantly and mashing sweet potatoes against sides of saucepan, until thick and shiny, 15 to 20 minutes.

Remove saucepan from heat and whisk in cream mixture until fully incorporated.

Strain mixture through fine-mesh strainer into bowl, using back of ladle or spatula to press solids through strainer.

Whisk mixture, then, with pie still on sheet, pour into warm crust. Bake for 10 minutes. Reduce oven temperature to 300 degrees and continue to bake until edges of pie are set and center registers 175 degrees, 20 to 35 minutes longer, rotating sheet halfway through baking. Let pie cool completely on wire rack, about 4 hours. Serve.