Toss apples with sugar, cornstarch, cinnamon, nutmeg, and lemon juice in a large bowl; set aside.
Mix flour and salt in a large bowl. Cut in shortening until mixture resembles fine crumbs. Add water 1 Tbsp. at a time, mixing lightly with a fork until flour mixture is evenly moistened and clings together when pressed into a ball. Divide the dough in half, shape each half into a 1/2 inch thick rounds. Wrap each dough round in plastic wrap; refrigerate 15 minutes.
Place 1 dough round between two large sheets of plastic wrap; roll out dough with a rolling pin. Work from center of dough to the edge, rotating dough to keep circular shape. Turn dough over, continue rolling until dough round is 2 inches larger than the diameter of inverted 9-inch pie plate. Peel off the top piece of plastic wrap and invert dough into pie plate. Peel off the remaining piece of plastic wrap; press dough evenly onto bottom and up side of pie plate, be careful not to stretch dough. Trim dough to edge of pie plate with a sharp knife.
Fill with prepared apple see filling.
Roll out remaining dough round, using the same method as listed above. Place crust evenly over top of filling in pie plate. Trim top crust about 1/2 inch beyond the edge of pie plate. Fold edge of top crust under the edge of the bottom crust, pinch edges together to form a ridge, flute edges. Cut several slits in center of pie to allow steam to escape.
Preheat oven to 400º. Bake for 45-50 minutes, or until juices form bubbles that burst slowly. Cool.