Mix together flour and salt in mixer (on low).
Shred cold butter with cheese grater, add to mixer. Mix until till pieces are pea size.
Add water very slowly; mix. Continue adding small amounts of water at a time, till all the dough is moistened. Dough will start to come together, and you're done mixing.
On lightly floured surface, flatten 1 dough ball. Roll from center to edges into 12-inch circle.
To transfer pastry, wrap it around the rolling pin; unroll into a 9-inch pie plate. Ease pastry into pie plate, being careful not to stretch pastry.
Roll remaining dough into a circle about 12 inches in diameter. Cut slits to allow steam to escape. Place remaining pastry on filling; trim ½ inch beyond edge of plate. Fold top pastry under bottom pastry; crimp edge as desired.
Note: even though this is "double crust," I often aim for 1.5x when making one pie, 3x for two pies, 4x for 2 deep dish pizzas.