Instructions

for the crust

Whisk ice water and sour cream together in bowl. Process flour, sugar, and salt in food processor until combined, about 5 seconds. Scatter butter over top and pulse until butter pieces are no larger than peas, about 10 pulses. Add ice-water mixture and pulse until dough forms clumps and no dry flour remains, about 15 pulses, scraping down sides of bowl as needed. (Dough will be loose and have texture of wet sand.)
Transfer dough to counter and knead briefly until dough comes together. Divide dough in half and form into two 5-inch disks, pressing any cracked edges back together. Wrap each disk in plastic wrap and refrigerate for 1 hour. (Wrapped dough can be refrigerated for up to 2 days or frozen for up to 1 month. If frozen, let dough thaw completely on counter before rolling.)
Let chilled dough sit on counter to soften slightly before rolling, about 10 minutes. Roll 1 dough disk into 12-inch round on lightly floured counter. Loosely roll dough around rolling pin and gently unroll it onto 9-inch pie plate, letting excess dough hang over edge. Ease dough into plate by gently lifting edge of dough with your hand while pressing dough into plate bottom with your other hand. Trim overhanging dough as needed to ¼ inch beyond lip of plate. Wrap dough-lined plate loosely in plastic and refrigerate until dough is firm, at least 30 minutes. Roll second dough disk into 12-inch round on lightly floured counter, then transfer dough round to parchment paper–lined baking sheet; cover with plastic; and refrigerate until firm, at least 30 minutes.

for the filling

Meanwhile, peel, core, and halve apples, then slice each half into ¼-inch-thick wedges. Combine apples, granulated sugar, and salt in Dutch oven. Cover and cook over medium heat, stirring often, until apples are completely tender but still hold their shape (some pieces should begin to turn translucent), 15 to 20 minutes. Drain apples in colander set over large bowl; let sit for 5 minutes to allow liquid to drain. Reserve ½ cup liquid in bowl and discard any excess liquid. Transfer apples to rimmed baking sheet and let apples and liquid cool completely, at least 30 min-utes or up to 2 hours.
Add brown sugar, cornstarch, vanilla, lemon zest and juice, cinnamon, allspice, and ginger to bowl with reserved apple liquid and whisk until smooth. Add apples and, using rubber spatula, fold into sugar mixture until evenly coated. Spoon apple mixture (including all liquid) evenly into chilled pie shell. Remove second dough round from parchmentand place over filling, then trim to ¼ inch beyond lip of plate.
Adjust oven rack to lowest position and heat oven to 450 degrees. Pinch edges of top and bottom crusts firmly together (if dough is too firm to pinch together, let sit for a few minutes until softened). Tuck overhanging dough under itself; folded edge should rest on lip of plate. Crimp dough around edge of plate using your thumb and forefinger (crimps should have sharp edges and pointed tips). Using paring knife, cut four 2-inch slits in top of dough. Beat egg and brush surface of dough with beaten egg, then sprinkle evenly with remaining 1 tablespoon granulated sugar.
Set pie on clean rimmed baking sheet and bake for 15 minutes. Reduce oven temperature to 375 degrees and continue to bake until crust is deep golden brown, about 35 minutes longer. Transfer pie to wire rack and let coolfor at least 4 hours or preferably overnight. Serve.TO MAKE AHEAD: Prepare pie through step 6, butdo not brush with egg wash or sprinkle with sugar. Freeze pie for 2 to 3 hours, then wrap tightly in double layer of plastic wrap, followed by layer of aluminum foil. Freeze wrapped pie for up to 2 weeks. When ready to bake, remove pie from freezer, remove foil and plastic, brush with beaten egg, sprinkle with sugar, and bake 5 to 10 minutes longer than indicated in step 7, after lowering oven temperature.