On a lightly floured surface, use your hands to slightly flatten Pastry for Single-Crust Pie. Roll dough from center to edge into a circle about 12 inches in diameter. To transfer pastry, wrap it around the rolling pin. Unroll pastry into a 9-inch pie plate. Ease pastry into pie plate, being careful not to stretch pastry. Trim pastry to 1/2 inch beyond edge of pie plate. Fold under extra pastry. Crimp edge as desired. Do not prick pastry.
For filling, in a large bowl, stir together the 3/4 cup sugar, the 2 tablespoons flour, and the salt. In a small bowl, beat the eggs lightly; stir in sour cream and vanilla. Add to sugar mixture, stirring until combined. Add blueberries and gently stir until coated.
Tranfer filling to pastry-lined pie plate. To prevent overbrowning, cover edge of the pie with foil. Bake in a 375 degree F oven about 30 minutes or until set about 2 inches in from edge.
Meanwhile, for the topping, in a medium bowl, stir together the 1/2 cup flour and the 1/2 cup sugar. With a pastry blender, cut in cold butter until mixture resembles coarse crumbs. Stir in the almonds. Remove foil from edge of pie. Carefully spoon crumb mixture evenly over filling.
Bake about 25 minutes more or until top is slightly puffed and golden brown. Makes 8 servings.
In a medium bowl stir together flour and salt. Using a pastry blender, cut in shortening until pieces are pea size. Sprinkle 1 tablespoon cold water over part of the flour mixture; toss gently with a fork. Push moistened dough to side of bowl. Repeat with additional cold water, 1 tablespoon at a time, until all of the flour mixture is moistened. Shape into a ball.