Ingredients
For the Crust:
1 1/4 cups all-purpose flour, plus more for work surface
3/4 teaspoon kosher salt
1 1/2 teaspoons granulated sugar
6 tablespoons unsalted butter, cold and cut into pieces
3 tablespoons solid vegetable shortening, cold
3 to 6 tablespoons ice water
For the Filling:
1 pound Cortland, Empire or McIntosh apples
2 pounds Granny Smith apples
1/4 cup fresh lemon juice
1/4 cup granulated sugar
2 1/2 teaspoons ground cinnamon
1/2 cup (about 2 ounces) walnuts, finely chopped
For the Topping:
1 cup all-purpose flour
1/4 cup packed dark brown sugar
1 teaspoon ground cinnamon
Pinch of kosher salt
8 tablespoons (1 stick) unsalted butter, cold and cut into pieces
Preparation
Make the Crust: Combine the flour, salt, and sugar in a food processor. Add the butter and shortening and pulse to form a coarse crumble. While the motor is running, add the ice water (1 tablespoon at a time) until the dough just comes together. Turn out onto a lightly floured surface and knead just until smooth. Shape into a disk and wrap in plastic. Refrigerate for 45 minutes. Then, on a lightly floured surface, roll the dough into a circle about 14 inches in diameter and place in a 9 inch pie plate. Using your fingers, fold over any overhand and crimp the edge. Refrigerate until ready to use.
Make the Filling: Heat oven to 375 degrees F. Peel, core, and slice all the apples 1/4 inch thick. Gently toss them in a bowl with the lemon juice, sugar and cinnamon. Spoon into the crust and sprinkle the walnuts over the top.
Make the Topping: Combine the flour, sugar, cinnamon and salt in a food processor. Add the butter and pulse to form a medium crumble (with pieces about the size of peas). Sprinkle the topping over the apples and walnuts. Bake for 1 hour, or until the crust is golden brown and the apples are tender.
