1 cup (2 sticks) unsalted butter, cut into 16 pieces and kept cold
3/4 cup cold water, approximate
Mix the dry ingredients in a medium bowl, add the butter, which has been cut into small pieces and work the flour and butter together by smearing together with your thumb and index finger until the butter is the size of peas.
Alternatively, use a pastry blender, electric mixer or food processor, but be very cautious of over developing the dough when you add water with the appliances.
Water is always given as an approximation; it depends on how much moisture is in the flour. Use only cold water to keep the butter from getting too soft. Add about half the water at first and just toss the flour and water together. Pick up a small handful of the dough and press together. If it falls apart, add more water, toss and check. Keep this up until the dough holds together with no crumbling.
Divide the dough in half, it’s loose and crumbly because you haven’t forced it together yet, and scoop each half onto a large piece of plastic wrap. Gently form a mound and wrap the dough.
Push the mound down with the palm of your hand and form a disc. Refrigerate at least two hours or overnight to hydrate the flour.
Freezes well. Freeze as a disc or roll out and freeze as a rolled up sheet. See video here.