Sift the flour and salt into a large mixing bowl. Incorporate the butter pieces and shortening by hand, working the fat into the flour with your fingertips until the dough starts to come together and form small pea-shaped pieces. Work the ice water into the dough with your fingers until it just comes together, being careful not to overmix.
Form the crust into a disk, wrap tightly in plastic wrap, and place in the refrigerator to rest for at least 30 minutes before rolling out to fit into a pie pan.
Yield: One 9- or 10-inch piecrust