In a large bowl, stir together the flour, sugar, and salt. Using a pastry blender or two knives, begin to cut the butter into the flour. While the butter is still in large pieces, add the shortening to the bowl and continue to cut the fat into the flour until most pieces are the size of large peas.

With a big fork or rubber spatula, stir in 5 to 6 tablespoons ice water, 1 to 2 tablespoons at a time, until the mixture is moist enough to hold together when pressed--it'll still look shaggy at this point.

Gently gather and press the dough together and then form it into a disk with well-floured hands, handling it only enough that the edge of the disk is reasonably together and smooth. Wrap the dough in plastic and chill for at least 60 minutes before rolling, preferably 2 to 4 hours.

Roll the dough out on a lightly floured surface (parchment on a counter also works great) into a 13-inch circle. The dough will be about 1/8 inch thick. Gently transfer the dough to a 9-inch metal, glass, or ceramic pie plate (I like to fold the dough in half, and unfold it into the pan). Do not stretch the dough as you line the pan, or it will spring back when baked. Trim the overhanging dough to 1 inch from the edge of the pan. Roll the overhanging dough over itself into a cylinder that rests on the edge of the pie pan. Crimp the edge of the dough and prick the sides and bottom of the crust all over with a fork. Refrigerate until firm, about 1 hour. This will relax the dough and help prevent the edge from caving in.

Position a rack in the center of the oven and heat the oven to 425 degrees F. Line the chilled pie shell with foil and fill it with pie weights or dried beans. Bake for 15 minutes; remove the foil and pie weights. Reduce the oven temperature to 375 degrees F. Bake until the bottom looks dry but is not quite done and the edges are light golden, 5 to 7 minutes more.