Preheat oven to 450 degrees F. Prepare Pastry for Double-Crust Pie. On a lightly floured surface, slightly flatten one portion of dough. Roll dough from center to edge into a 12-inch circle. Wrap pastry circle around rolling pin; unroll into a 9-inch pie plate. Ease pastry into pie plate without stretching it. Trim pastry even with edge of pie plate.
Roll the remaining dough until 1/8 inch thick. Cut into 1/2- to 3/4-inch shapes with small cookie or hors d'oeuvre cutters. Brush edge of pastry shell with water; arrange cutouts around edge of shell. Do not prick pastry. Line pastry with a double thickness of foil. Bake for 8 minutes. Remove foil. Bake for 4 to 5 minutes more or until pastry is set and dry. Remove from oven. Reduce oven temperature to 350 degrees F.
Meanwhile, for filling, in a large skillet heat 1 tablespoon of the butter over low heat until melted. Cook about 3 minutes or until golden brown. Add oats and walnuts. Cook and stir for 3 to 4 minutes or until toasted; cool.
In a large microwave-safe bowl microwave the remaining butter on 100 percent power (high) for 30 to 45 seconds or until melted. Stir in corn syrup; whisk in eggs, pumpkin butter, vanilla, cinnamon, nutmeg, and salt. Stir in oat mixture. Pour filling into pastry shell.
Cover edge of pie with foil to prevent overbrowning. Bake for 45 to 50 minutes or until filling is set. Cool on a wire rack. If desired, serve with Sweetened Whipped Cream or vanilla ice cream.
Sweetened Whipped Cream
In a chilled mixing bowl combine whipping cream, sugar, and vanilla. Beat with an electric mixer on medium speed until soft peaks form (tips curl).
Pastry for Double-Crust Pie
In a large bowl stir together flour and salt. Using a pastry blender, cut in shortening and butter until pieces are pea-size. Sprinkle 1 tablespoon ice water over part of the flour mixture; toss gently with a fork. Push moistened dough to side of bowl. Repeat with additional ice water, 1 tablespoon at a time, until all of the flour mixture is moistened. Gather mixture into a ball, kneading gently until it holds together. Divide dough in half. Shape each portion into a ball.