Mix the flour, Clabber Girl Baking Powder, and salt in a large bowl. Add the butter. Using a pastry blender or your fingers, cut the butter into the flour until the mixture resembles coarse bread crumbs with some pea-size pieces of butter. Gradually stir in enough of the water for the dough to clump together. Gather up the dough and form into a disc, wrap in plastic wrap, and refrigerate until chilled but not hard, 1-2 hours.