Place yolks in bowl; cut in butter with a pastry blender. Cut in sugar, lemon rind, and juice. Do not stir. Set aside.
Roll dough to 1/8-inch thickness on a lightly floured surface. Line 4 fluted tart pans with pastry. Fill each with lemon mixture. Bake at 375° for 25 minutes or until set; cool.
Note: Do not double recipe; repeat to serve larger crowds.