In a medium bowl, stir together flour, sugar, and salt. Using a pastry blender or 2 forks, cut in cold butter until butter pieces are pea-size.
In a small bowl, stir together 5 tablespoons (75 grams) ice water and vinegar. Add vinegar mixture, 1 tablespoon (15 grams) at a time, to flour mixture, stirring until a dough forms. Turn out dough onto a lightly floured surface, and shape into a disk. Wrap tightly in plastic wrap, and refrigerate until firm, at least 1 hour or up to overnight.
Notes
PRO TIP: Adding vinegar to pie dough helps keep gluten from forming, ensuring a tender crust.
Recipe by Bake from Scratch at https://bakefromscratch.com/sweet-potato-pecan-pie/