Heat oven to 425°F. In a bowl, combine sugar, pumpkin-pie spice, salt, and pepper. Whisk in eggs, vanilla, pumpkin, and evaporated milk. Place piecrust on baking sheet, pour pumpkin mixture into crust, and bake 20 minutes. Turn oven down to 350°F; bake 55 minutes more, or until knife inserted in center comes out clean. Let cool on wire rack 2 hours. Refrigerate if serving the next day. Serve at room temperature with whipped cream.