Combine the ice water and vinegar in a small measuring cup. With the mixer running, slowly add the vinegar mixture to the flour mixture, adding just enough for the mixture to come together into shaggy clumps. (If you’ve added all the liquid and the dough is still not holding together, add enough cold water, 1 teaspoon at a time, until it does cling together.) ☞ TESTER TIP: Be careful not to overmix the dough, or it will become tough.