FOR THE CRUST:
In the bowl of a food processor, pulse together the flour and salt just to combine. Drop in the butter pieces and run the motor until crumbs the size of lima beans form. Add the ice water, 1 tablespoon at a time, and pulse the motor just until the dough comes together, taking care not to overtax the dough.
Turn the dough out onto a sheet of plastic wrap and divide it into half. Press each half together to make a flat disc. Wrap in the plastic and chill in the refrigerator for at least 3 hours and up to 3 days. Or you can freeze the dough up to 6 months.
FOR THE FILLING:
Roll the discs of dough into circles about ¼-inch-thick. Use one to line a 9-inch pie pan and chill in the refrigerator for 30 minutes and up to overnight. Place the other on a baking sheet and chill until needed.
When the piecrust is in the oven, prepare the filling. In a large bowl, mix together the apples, brown sugar, flour, cinnamon, nutmeg, vanilla, ginger, and salt.
When the piecrust is ready, remove the foil and pie weights and fill with the apple mixture. Dot the apples with the butter pieces. Place the remaining circle of dough on top, fluting the edges and cutting steam vents. Brush the raw dough with milk and sprinkle with cinnamon sugar. Bake for 45 to 50 minutes, until the juices are bubbling and the crust is golden brown. Transfer the pie to a wire rack to cool for 30 minutes before serving.