Begin by making the crust. Stir flour and salt together in a medium mixing bowl. Add the shortening to the bowl, and cut it into the flour mixture using a pastry cutter or a couple of knives, until the mixture resembles fine crumbs. Add cold water, a tablespoon at a time, stirring between each addition, just until a dough forms. Shape the dough into a ball and wrap in plastic. Place it into the refrigerator to chill while you prepare the filling.
Make the filling by placing all ingredients into a large mixing bowl. Stir with a large spoon until ingredients are uniformly mixed and all apple slices are coated in spice mixture.
Preheat the oven to 400°F.
Coat a work surface with flour, then turn the dough onto the floured surface. Use a lightly floured rolling pin to roll the dough into a circle, about 14 inches in diameter. Carefully place the dough into a 9 inch pie plate, covering the edges of the plate. Trim any excess dough, then use a fork or your fingers to create scallops in the upper edge of the dough.
Place the filling into the crust, distributing relatively evenly. It will form a bit of a dome.
Make the crumble topping by stirring flour, brown sugar, cinnamon and salt together in a small bowl. Add vegetable shortening to the bowl, and cut it in with a fork or a couple of knives, until the mixture is crumbly. Spread in an even layer over the filling.
Bake for about 30 minutes, or until the crust and crumble topping begin to brown. Lower heat to 350°F and cover the pie with foil. Bake for about 20 minutes more, or until the filling becomes bubbly. Remove the pie from the oven and transfer to a cooling rack to cool. Serve with ice cream or coconut whipped cream.