How to Make It
In a food processor, combine 2 1/2 cups of the flour with 1 tablespoon of the granulated sugar and 1 teaspoon of kosher salt and pulse to mix. Add the butter and pulse in 1-second bursts until the mixture resembles coarse meal. Drizzle the ice water over the mixture and pulse in 1-second bursts until the dough just comes together. Turn the dough out onto a work surface, gather any crumbs and pat into 2 squares. Wrap the squares in plastic and refrigerate until chilled, about 45 minutes.
Preheat the oven to 400°. On a floured work surface, roll out 1 piece of the dough to a 12-inch square. Slide the dough onto a large sheet of parchment paper, then slide onto a large baking sheet. Repeat with the second piece of dough. Refrigerate for 15 minutes.
Slide 1 square of dough onto a work surface. In a large bowl, toss the pears with the cranberries, ginger, 1/2 teaspoon of salt and the remaining 1/2 cup of granulated sugar and 1/4 cup of flour. Spread the fruit evenly on the dough square on the baking sheet, leaving a 1-inch border. Ease the other square of dough on top of the fruit. Fold over the edge and crimp decoratively all around to seal. Brush the pie with the egg wash and sprinkle with turbinado sugar. Cut 16 small slits in the top and freeze for 15 minutes.
Bake the pie for about 50 minutes, until golden and the pears are tender; rotate halfway through baking. Let cool. Cut the pie into squares and serve.