Preheat oven to 350 degrees.
In a large mixing bowl, combine flour and sugar. Using a party cutter or food processor, cut the butter into the flour mixture until it resembles coarse sand. Add the lemon zest and stir to combine. Add egg yolk and whole egg, and knead together until smooth.
Transfer the dough to a lightly floured work surface and divide the dough into two balls, roughly 1/3 and 2/3s. Press the larger ball evenly into the bottom and sides of a 9-inch metal tart pan with a removable bottom. Spread apricot preserves evenly across the surface of the crust.
Roll out remaining dough, and cut into 8 even ropes. Lay the ropes across the surface of the tart, creating a lattice pattern. Press the ends firmly into the edge of the crust and trim off any excess.
Press ends firmly against the side crust to seal. Bake tart in preheated oven 35 to 40 minutes or until the crust is golden brown. Remove from oven and cool on wire rack. Serves 6 to 8.