Add the flour, sugar, and salt to the bowl of a food processor. Pulse once or twice to combine.
Add the vegan butter. Pulse a few times, just until the butter mixes into the flour, forming a sandy mixture with some pea-sized pieces.
Add the vinegar and water. Pulse 60 to 90 seconds just until it comes together into a ball of dough. It’ll start out looking like wet sand, and comes together into a ball during the last few seconds of pulsing.
Dump the dough onto a lightly floured counter. Divide the dough into 2 equal pieces, and shape into 1-inch thick, round disks. Use immediately, or wrap tightly in plastic film, and store in fridge until ready to use (up to three days).