In a large bowl, mix the flour, salt, and sugar. Cut in the chilled, diced butter until the mixture resembles coarse crumbs.

Stir in the ice water, a tablespoon at a time, until the mixture forms a ball. Divide the dough into two halves, shape into disks, wrap in plastic, and refrigerate for at least 1 hour.

In another bowl, toss the sliced apples with sugar, flour, and cinnamon until evenly coated. Let this sit while you roll out the dough.

Preheat your oven to 425°F (220°C).

Roll out one dough disk and fit it into a 9-inch pie plate. Fill with the apple mixture, dot with the diced butter, and cover with the second rolled dough. Trim the edges and crimp to seal, then cut slits in the top to allow steam to escape.

In a small bowl, whisk together the egg yolk and milk; brush this mixture over the crust for that golden finish.

Place your pie on a baking sheet and bake for 15 minutes in the hot oven. Reduce the temperature to 350°F (175°C) and continue baking for an additional 25-30 minutes or until the apples are soft and the crust is golden brown.

Allow the pie to cool for at least an hour before serving, letting the filling all set together nicely.