Position oven rack to lowest position.

Preheat oven to 425°.

To prepare filling, combine first 6 ingredients in a large bowl, stirring with a whisk. Add pumpkin, and stir with a whisk until smooth.

To prepare crust, roll dough into an 11-inch circle; fit into a 9-inch pie plate coated with cooking spray. Fold edges under and flute.

Pour pumpkin mixture into the crust. Place pie plate on a baking sheet. Place baking sheet on lowest oven rack. Bake at 425° for 10 minutes. Reduce oven temperature to 350° (do not remove pie from oven); bake an additional 50 minutes or until almost set. Cool completely on wire rack.

To prepare topping, beat cream with a mixer at high speed until stiff peaks form. Add the amaretto and powdered sugar, and beat until blended. Serve with pie.