Preheat oven to 450 degrees F. Prepare Pastry for Single-Crust Pie. On a lightly floured surface, use your hands to slightly flatten 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 to 1/2 inch beyond edge of pie plate. Fold under extra pastry. Crimp edge as desired. Prick bottom and side of pastry with a fork. Line pastry with a double thickness of foil. Bake for 8 minutes. Remove foil. Bake for 5 to 6 minutes more or until pastry is golden. Cool on a wire rack. Reduce oven temperature to 350 degrees F.
For streusel topping, in a food processor combine 1/3 cup flour, oats, the 1/4 cup almonds, the 1/4 cup butter, the 2 tablespoons granulated sugar, brown sugar, cinnamon, the 3/4 teaspoon nutmeg, and 1/4 teaspoon salt. Cover and process until mixture resembles coarse crumbs. (Or, chop almonds; in a medium bowl combine almonds, flour, oats, granulated sugar, brown sugar, cinnamon, nutmeg, and salt. Using a pastry blender, cut in butter until mixture resembles coarse crumbs.) Set aside.
In a small saucepan heat the 3/4 cup butter over medium-low heat until melted. Continue heating until butter turns a light golden brown. Remove from heat. In a medium bowl whisk together eggs, the 1 cup granulated sugar, 1/3 cup flour, vanilla, and 1/4 teaspoon salt. Whisk in browned butter; set aside.
In a large bowl toss together peaches, the 1/2 cup almonds, lemon peel, and the 1/4 teaspoon nutmeg. Transfer mixture to baked pastry shell. Pour browned butter mixture over peach mixture. Top with streusel topping. To prevent overbrowning, cover edge of pie with foil.
Place pie on a baking sheet. Bake for 50 to 55 minutes or until filling is set and golden. Cool on a wire rack. Store, covered, in the refrigerator. Makes 8 servings.
Pastry for Single-Crust Pie
Stir together flour and salt. Using a pastry blender cut in shortening until pieces are pea-size. Sprinkle 1 tablespoon of the water over part of the mixture; gently toss with a fork. Push moistened dough to side of the bowl. Repeat moistening dough, using 1 tablespoon of the water at a time, until all the dough is moistened. Form dough into a ball. On a lightly floured surface, use your hands to slightly flatten dough. Roll dough from center to edge into a circle about 12 inches in diameter.