Pie Crust: In your food processor, place the flour, salt, and sugar and process until combined. Add the butter and process until the mixture resembles coarse meal (about 10 seconds). Sprinkle about 2 - 3 tablespoons of water over the flour mixture and process the dough just until it holds together when pinched. If necessary, add more water. 

Turn your dough onto your work surface, gather it into a ball, and flatten into a disk. Cover with plastic wrap and refrigerate for about one hour or until firm. This will chill the butter and relax the gluten in the flour. 

Preheat your oven to 375 degrees F (190 degrees C). Place the oven rack at the lowest level and place a baking sheet on the rack before preheating the oven (this will catch an drips while the pie is baking).

After the dough has chilled sufficiently, remove from the fridge and place it on a lightly floured surface. Roll the pastry into a 12 inch (30 cm) circle. (To prevent the pastry from sticking to the counter and to ensure uniform thickness, keep lifting up and turning the pastry a quarter turn as you roll (always roll from the center of the pastry outwards).) Loosely roll the pastry around your rolling pin and transfer to a 9 inch (23 cm) pie pan. Brush off any excess flour and trim the edges of the pastry to fit the pie pan. Crimp the edges if desired. Cover with plastic wrap and place in the refrigerator to chill while you make the Crumble Topping and Apple Filling.

Crumble Topping: Place the flour in a large bowl. Whisk in the sugar, ground cinnamon, and salt. Then cut the butter into the mixture until it's crumbly (looks like coarse meal). (This can be done with a pastry blender, two knives or your fingertips.)  Set aside while you prepare the filling.

Apple Filling: In a large bowl toss the thinly sliced apples with the lemon juice (this will prevent the apples from browning). Then place the apple juice concentrate in a medium saucepan. Whisk in the cornstarch until there are no lumps. Then whisk in the sugar and butter. Place over medium heat and bring to a boil. Boil the mixture, whisking constantly, for about two to three minutes or until the mixture has become quite thick, clear, and gel-like. Remove from heat and add to the apple slices, making sure that all the apple slices are coated with the mixture.

Pour the apples and their syrup into the chilled pie crust. Sprinkle the top of the apples with the Crumble topping. Bake for about 45 - 50 minutes or until the Crumble Topping has nicely browned and the apple juices start to bubble around the edges of the pie (the apples should also feel tender (not mushy) when a toothpick or sharp knife is inserted into the apple slices). Remove the pie from the oven and place on a wire rack to cool for about 3-4 hours before cutting. This will allow the juices to thicken. Serve warm or at room temperature with vanilla ice cream or softly whipped cream. Store at room temperature for 2 to 3 days or in the refrigerator for 4 to 5 days.

Makes about 8 - 10 servings.