for the Crust
2 1/2 cups all purpose flour
1 tablespoon sugar
3/4 teaspoon salt
10 tablespoons (1 1/4 sticks) chilled unsalted butter, cut into 1/2-inch pieces
1/3 cup chilled solid vegetable shortening, diced
6 tablespoons (or more) ice water
for the Filling
1/2 cup sugar
2 tablespoons all purpose corn starch
1 tablespoon lemon juice
2 teaspoons grated lemon peel
3/4 teaspoon ground cardamom
3 pounds Bartlett pears, peeled, cored, very thinly sliced
1 egg yolk
Blend flour, sugar and salt in processor. Add butter and shortening and cut in using on/off turns until mixture resembles coarse meal. Add 6 tablespoons ice water and process until moist clumps form, adding more water by teaspoonfuls if dough is dry. Gather into ball and flatten into a disk. Wrap in plastic; chill 2 hours.
Position rack in lowest third of oven and preheat to 400F. Mix together sugar, corn starch, lemon juice, grated lemon peel, and cardamom in a medium bowl. Add pears and toss to blend.
Roll out dough disk on floured surface to 12-inch round. Transfer to 9-inch-diameter tart pan, Fold edge under, forming high-standing rim; crimp. Add filling by placing each apple slice upright individually. This is very time consuming but creates the neat swirl pattern. Using a pastry brush, paint egg yolk over the crust edge. Bake pie 10 minutes at 400F. Reduce oven temperature to 375F. Continue baking until juices bubble thickly and crust is deep golden, covering edges with foil if browning too quickly, about 1 hour.
Let pie cool 1 hour before cutting.