How to Make It
Into a medium bowl, sift the flour with the confectioners’ sugar and salt. Using your fingertips, rub half of the lard into the flour mixture until it resembles coarse meal. Rub the remaining lard and the butter into the flour mixture until pea-size pieces remain. Sprinkle with the ice water and mix with a fork until the dough comes together. On a lightly floured work surface, pat the dough into a 1-inch-thick disk. Wrap with plastic and chill until firm, about 1 hour.
On a lightly floured work surface and using a lightly floured rolling pin, roll out the dough into a 14-inch circle about 1/8 inch thick. Ease the dough into a 9-inch fluted tart pan with a removable bottom (2 inches deep) and trim the overhang. Prick the dough all over with a fork and freeze until firm, 1 hour.
Preheat the oven to 375°. Line the frozen pie shell with parchment paper and fill with pie weights or dried beans. Bake for 25 minutes, until the edges are lightly golden. Remove the paper and bake for 15 minutes longer, until the shell is golden. Transfer to a rack and let cool completely, 3 hours.
Preheat the oven to 350°. In a blender, combine the Meyer lemon, superfine sugar, butter, vanilla and eggs and puree until smooth. Pour the mixture into the tart shell. Bake for 40 minutes, until the filling is set. Transfer the tart to a rack and let cool to room temperature, 3 hours. Serve at room temperature or chilled.