In a large bowl, mix the flour and salt. Add the butter and work the butter into the dough until pieces are roughly the size of peas. Stir in the ice water a tablespoon or two at a time, just until the mixture forms a workable dough. Turn the dough out onto a lightly floured surface and press into a round. Chill in the refrigerator for at least 30 minutes or up to 1 hour.

Rinse, peel, and core the apples. Cut into slices about ¼ inch wide and transfer to a large bowl. Add the flour, cinnamon, lemon juice and zest, brown sugar, and salt, and mix to combine.

In a medium bowl, mix the flour, granulated sugar, brown sugar, cinnamon, and salt. Add the butter and work into the flour mixture until it resembles coarse sand. Chill in the refrigerator until ready to use.

Heat the oven to 400°F. On a well-floured surface, roll the crust to about ⅛ inch thick. Transfer to a 12-inch cast-iron skillet. Unroll and lightly press into the edges, trimming the edges so they are flush with the rim of the skillet.

Pour the apple filling into the crust. Top with the crumb topping, mounding in the middle and lightly packing it down over the apples.

Bake for about 30 minutes, until the top is golden brown. Reduce the oven temperature to 350°F and continue to bake for 40 to 45 minutes more, until the apples are tender when pierced with a knife. If the topping is browning too quickly, cover the pie with foil.

Let cool until warm or room temperature.