Crust:
1 3/4 cups flour
1/4 cup sugar
1 teaspoon cinnamon
1/2 tsp salt
1/2 cup plus 1 tablespoon butter
1/4 cup water
Filling:
1 egg
2 tablespoons vanilla
1 2/3 cups sour cream
1 cup sugar
1/3 cup flour
pinch of salt
8 medium peaches, peeled, sliced
Topping:
1 cup chopped walnuts
1/2 cup flour
1/3 cup firmly packed brown sugar
1/3 cup sugar
1 tablespoon cinnamon
pinch of salt
1/2 cup butter at room temperature
Combine flour, sugar, cinnamon and salt in bowl. Cut in butter until mixture resembles coarse meal. Add water and toss gently with fork until evenly moistened. Roll a circle slightly larger than a deep 10-inch pie plate. Ease pastry into pan.
Preheat oven to 450 degrees. Lightly beat egg then mix in vanilla and sour cream. Blend in sugar, flour and pinch of salt, then fold in sliced peaches. Spoon into crust and bake 10 minutes. Reduce oven temperature to 350 degrees and continue baking until filling is slightly puffed and golden brown, approximately 40 minutes.
While pie is baking in oven, in a mixing bowl combine walnuts, flour, sugars, cinnamon and salt; mix well. Blend in butter until mixture is crumbly, spoon over pie after cooked and bake an additional 15 minutes.