To make the dough: Whisk together the flours and salt. Work in the butter, leaving some intact chunks as large as your thumbnail., Sprinkle the water over the dry ingredients while stirring with a fork., When the mixture feels damp and sticks together when squeezed, turn it out onto a piece of parchment and use the paper to fold it over on itself until it comes together. Spritz any particularly dry spots with cold water., Pat the dough into a disk 3/4" thick, rounding the edges so they're smooth. Wrap and chill the dough for 30 minutes. Roll it into a 13" circle. Place the dough in a 9" pan, trim and crimp the edges, and place the pan in the refrigerator., To prebake the crust: Preheat the oven to 400°F. Take the chilled crust from the refrigerator, line it with foil or parchment, and place pie weights (or dried beans or uncooked rice) inside., Place the pie pan on a baking sheet and bake the crust for 15 to 20 minutes, until the top edges begin to take on some color. Remove from the oven and remove the parchment and weights from the pan., Prick the bottom and sides of the dough with a fork and return the crust to the oven for 10 to 15 minutes, until it no longer looks wet and begins to take on some color. If the dough puffs while baking, prick it with a fork to release steam and deflate it., Remove from the oven and let cool completely before filling.