For the crust:
1.Put the flour, sugar, vinegar and 1/2 teaspoon salt in a food processor, and pulse to combine.
2. Add the coconut oil in small spoonfuls, and pulse until the largest pieces are pea-sized.
3. Add 4 tablespoons ice water, and pulse until evenly combined.
4. Squeeze a handful of the dough together; it should just hold its shape. If the mixture is too powdery, pulse in an additional 1 to 2 tablespoons ice water.
5. Turn the dough out onto a large piece of plastic wrap, pat into a 1/2-inch-thick disc and chill for at least 1 hour up to overnight.
6. To make rolling easier, let the dough soften up a bit-it should be slightly soft when pressed-at room temperature (this may take anywhere from 20 to 40 minutes depending on the temperature of your kitchen).
7. Roll the disc into a 12-inch round on a lightly floured surface or between two pieces of floured parchment paper. If the dough gets too warm, refrigerate it to firm it up.
8. Ease the crust into a 9-inch pie plate. Fold the overhanging dough under itself, and crimp the edge as desired. Chill for 30 minutes.
9. Position an oven rack in the center of the oven, and preheat to 180°C. Line the chilled pie crust with a large coffee filter or foil, and fill with pie weights.
10. Bake until the edges are lightly golden, 20 to 25 minutes. Remove the coffee filter or foil and weights, and continue baking until the crust is lightly golden all over, 15 to 20 minutes more.
11. Transfer to a rack, and let cool completely.
For the filling:
1. Process the pumpkin puree, tofu, sugar, cornstarch, cinnamon, nutmeg, vanilla and 1/4 teaspoon salt in a food processor until completely smooth, scraping down the sides of the bowl as needed.
2. Pour the filling into the par-baked pie shell, and bake until firm and set, 40 to 45 minutes.
3. Let cool completely on a rack. Chill for at least 2 hours up to overnight. Slice and serve.