Prepare the Crust

In a large mixing bowl, combine flour, sugar, and salt. Cut in the cold butter using a pastry cutter or your hands until the mixture resembles coarse crumbs. Gradually add ice-cold water, mixing gently until the dough comes together. Divide into two discs, wrap in plastic, and refrigerate for at least 30 minutes.

Make the Filling

In a large bowl, toss the apple slices with sugar, flour, cinnamon, nutmeg, allspice, and lemon juice. Let the mixture sit for 10 minutes to allow the flavors to meld.

Assemble the Pie

Roll out one dough disc to fit a 9-inch pie dish. Gently press it into the dish and trim any excess. Pour the apple filling into the crust, spreading it evenly. Roll out the second dough disc and place it over the filling. Trim, seal, and crimp the edges. Cut small slits in the top crust to allow steam to escape.

Bake the Pie

Preheat your oven to 375°F (190°C). Brush the crust with an egg wash (1 egg whisked with 1 tablespoon water) for a golden finish. Bake for 45-50 minutes or until the crust is golden brown and the filling is bubbling. Cool for at least 2 hours before serving.