Make the orange curd: In a small saucepan, whisk together yolks, sugar, zest, and juice. Cook over medium-low heat, whisking constantly, until thick enough to coat a spoon (about 5-7 minutes). Remove from heat and whisk in butter. Chill completely.

Make the crust: Combine flour, sugar, and salt in a bowl. Cut in cold butter until coarse crumbs form. Stir in egg yolk and ice water, 1 tablespoon at a time, until dough holds together. Shape into a disc, wrap, and chill 20 minutes.

Assemble: Roll out dough to ¼-inch thickness. Cut circles for cookie bases, then thin strips for lattice tops. Spoon a little orange curd onto each circle, then lay strips over top in a crisscross pattern. Optional: brush lattice with egg wash (1 beaten egg + 1 teaspoon water) and sprinkle with coarse sugar.

Bake: Bake on a silicone-lined sheet at 400°F for about 10-12 minutes, until edges are golden.

Cool: Let cool on the tray 5 minutes before transferring to a rack.