Make the dough: In a bowl, whisk together the salt, sugar, flour and cocoa. Use a pastry cutter to work in the butter, stopping when you have a mix of pea and kidney bean sized pats of butter. You can also do this in a stand mixer fitted with the spatula attachment.
Make a well in the center and pour in the water. Add the vinegar and 1 tsp vanilla to to the water and use your hands to bring the dough together (it will take quite a few ‘folds’; it’s a bit like kneading the dough but mostly you are trying to get into a dry, loose ball). If using a stand mixer, run the mixer on low until the dough starts to come together and clean the bowl. Wrap the dough in plastic wrap and set in the fridge to chill for at least two hours but up to 24 hours.
Shape the dough: on a lightly floured surface roll out the dough to about ½ cm thickness rounding it by rolling in different directions to create a circle. The dough should be about 3 inches wider than your pie pan (set your pie pan upside down on the pie crust to check it). Roll the crust gently onto the rolling pin and then lay it on the pie pan (no need to grease the pan). Using your fingertips gently press the dough into the bottom of the pan. Fold the outer edge over itself so you have a thick layer to shape. Shape the edges by pressing the dough between your index and thumb fingers on one hand, and your index finger on the other hand. Chill the crust in the fridge for at least an hour, but up to 4-6 hours (I have also done this overnight, it works out alright).
First blind bake: Preheat oven to 375 F. Set the pie on a cookie sheet and cover it completely with foil. You’ll need at least two sheets of foil to do this; every piece of the dough should be covered. Wrap the foil around the edges of the crust. Fill with pie weights or dried beans, all the way to the rim of the pie (I like to put a piece of parchment paper between the foil and beans so I can easily lift them out). Bake for 20 minutes. If you are filling the pie with something that needs to be baked, fill it then return it to the oven.
Second bake (for a fully baked crust): Remove the foil and dried beans and dock the pie crust with a fork all over. Return it to the oven and bake for another 15 minutes.
Video
Notes
Makes one 9” pie crust with a thick trim (equivalent to one and a half a regular pie crust).