- Crust:
- 2 cups all-purpose flour
- 2 tablespoons powdered sugar
- 1 teaspoon salt
- 3/4 cup cold butter, cut into 1/2-inch cubes
- 1 teaspoon vinegar
- 5 tablespoons ice water, or more if needed
- Filling:
- 1 (15 ounce) can pumpkin
- 3/4 cup light brown sugar, packed
- 2 teaspoons pumpkin pie spice
- 2 tablespoons flour
- 3 eggs, beaten
- 2 tablespoons Frangelico liqueur (optional)
- 1/2 cup sour cream
- Candied Hazelnut Topping:
- 2 tablespoons flour
- 1/4 cup light brown sugar, packed
- 1 tablespoon Frangelico liqueur (optional)
- 3 tablespoons cold butter, cut into 1/2 inch pieces
- 1/2 cup hazelnuts, peeled and chopped
- Crust: In a bowl, stir together flour, sugar and salt. Using a pastry blender, cut butter cubes into flour mixture until pieces are pea-size. Sprinkle vinegar over flour mixture, tossing with a fork. Sprinkle 5 to 6 tablespoons cold water, 1 tablespoon at a time, over flour mixture, tossing with a fork each time until dough is moistened and crumbly. Press crumbs firmly on bottom and up sides of a 9-inch pie plate.
- Filling: Preheat oven to 375 degrees F. In a bowl, stir together pumpkin, brown sugar, pumpkin pie spice, flour, eggs, Frangelico and sour cream; mix well. Pour into pie crust, fold narrow strip of foil over edges of crust to prevent over browning; bake 30 minutes.
- Meanwhile, make topping. In a bowl, combine flour, brown sugar and Frangelico. Cut in butter until crumbly. Stir in hazelnuts.
- Remove foil from pie and sprinkle with topping. Bake 15 to 20 minutes more or until knife inserted near center comes out clean. Cool on a wire rack.