Arrange rack in middle of oven. Preheat oven to 375°F. Wash and pierce potatoes all over with a fork. Wrap in foil; place on a rimmed baking sheet. Bake 60 minutes or until a fork pierces the flesh with ease. Set aside until cool enough to handle; slip off skins. (Cool and refrigerate up to 3 days in advance.) Lower oven temperature to 350°F. Fit dough into a 9-inch pie plate, fluting or crimping edges as desired; chill 30 minutes. Prick dough all over with tines of a fork. Fit a piece of foil into crust, leaving an overhang. Fill with pie weights or dried beans. Bake 20 minutes or until bottom of crust is dried out (foil will come away easily). Remove from oven; carefully remove foil and pie weights. Place sweet potatoes and melted butter in a food processor; pulse 5–6 times or until well combined (don’t overprocess or they’ll become gummy). You should have about 2 cups pureed sweet potatoes. Use a rubber spatula to scrape bottom of food processor. Add granulated and brown sugar, 1 Tbsp vanilla and next 9 ingredients (through orange zest); pulse until combined, about 10 times. Use spatula to scrape bottom of processor; pulse 2–3 more times. Remove processor bowl from machine; remove blade. Use spatula to stir mixture until smooth; fold in pecans. Pour filling into parbaked pie crust; smooth top. Bake 50–55 minutes or until filling is set. Remove from oven; cool completely. Refrigerate until ready to serve. Place cream, powdered sugar and remaining 1 tsp vanilla in bowl of a stand mixer fitted with a whisk attachment (or in a medium bowl, using a hand mixer). Whisk or beat on medium speed until soft peaks form. Reduce speed to slow; whisk or beat until stiff peaks form. Serve pie dolloped with whipped cream and, if desired, a cinnamon stick or dusting of ground cinnamon.