Combine flour and cold butter in a food processor until crumbly, then gradually add ice water until a dough forms. Divide the dough in half, flatten each into a disc, wrap, and refrigerate for at least 30 minutes.

Roll out one dough disc and carefully transfer it to a 9-inch pie plate, trimming any excess and crimping the edges as desired.

In a large bowl, combine sliced apples with sugar, cinnamon, and nutmeg, ensuring the apples are evenly coated.

Pour the apple mixture into the prepared pie crust, mounding it slightly in the center.

Preheat oven to 425°F (220°C). Roll out the second dough disc and place it over the apple filling, either as a solid top crust with vents or as a lattice, then crimp the edges to seal.

Bake for 15 minutes at 425°F (220°C), then reduce oven temperature to 375°F (190°C) and continue baking for another 35-45 minutes, or until the crust is golden brown and the filling is bubbly. Let cool completely before serving.