Instructions Prepare the crust: In a large bowl, mix the flour, salt, and sugar. Add the cold butter cubes and cut them into the flour mixture using a pastry blender or your hands until the mixture resembles coarse crumbs.
Mix Filling Ingredients: In a large bowl, combine the sliced apples with granulated sugar, brown sugar, cinnamon, nutmeg, allspice, lemon juice, and flour. Toss to coat the apples evenly.
Assemble the pie: Cut a few slits in the top crust to allow steam to escape. Brush the top crust with beaten egg and sprinkle with coarse sugar.
Bake the pie: Place the pie on a baking sheet to catch any drips and bake for 20 minutes.
Lower Temperature: Reduce the oven temperature to 375°F (190°C) and continue baking for an additional 40-50 minutes, until the crust is golden brown and the filling is bubbling.
Cool the Pie: Remove the pie from the oven and let it cool on a wire rack for at least 2 hours before serving. This allows the filling to set properly.