Make the filling. In a mixing bowl, stir together the peaches, cornstarch, sugar, salt, cinnamon, nutmeg, and lemon juice. Set aside.5 cups (1,020 g) peeled, diced peaches 2 Tablespoons cornstarch ½ cup (100 g) granulated white sugar ¼ teaspoon salt 1 teaspoon ground cinnamon ¼ teaspoon ground nutmeg 2 teaspoons lemon juice
Preheat oven. Preheat the oven to 425°F (220°C), and set a rack in the lower third of your oven.
Roll out the pie crust. On a floured work surface, roll out the dough into a 12” circle. Transfer the dough to a 9” pie dish. Tuck it in with your fingers, making sure it is smooth. Trim the excess, leaving about a 1-inch overhang. Fold the excess pie dough underneath, crimping the edges. Spoon the peach filling into the crust, leaving some of the liquid in the bowl. Refrigerate while you make the crumb topping. 1 single pie crust
Make crumble topping. In a small bowl, whisk together the flour, brown sugar, granulated sugar, cinnamon, and salt. Stir in melted butter until a crumbly mixture forms. Sprinkle the topping over the top of the peaches spreading to the edges. 1 cup plus 2 tablespoons (135 g) all-purpose flour ½ cup (107 g) packed light brown sugar ½ cup (100 g) granulated sugar ½ teaspoon ground cinnamon Pinch salt 6 tablespoons (3/4 stick, 85 g) unsalted butter
Bake the pie. Brush the edges of the pie crust with the prepared egg wash. Place the pie onto a large baking sheet and bake for 15 minutes. Reduce the oven temperature to 350°F and bake for an additional 45-50 minutes, until the crust edges is golden brown and the filling is bubbling. Cover the edges of the pie with a pie shield, or aluminum foil, if the edges or topping are browning too quickly.Allow the pie to cool for at least 3 hours before serving. Egg wash: 1 large egg beaten with 1 tablespoon water