Use cast-iron cookie stamps to leave imprints on this beautifully textured shortbread, which is flavored with tangy orange and lemon zests. The stamps, which are available online, are a fun way to shape and decorate cookies without much effort. (Don’t be afraid to be generous with the flour, on the cookie balls and on the stamps themselves, shaking off excess so you still get a clean imprint.) But if you don’t have stamps, you can roll and cut the dough using a simply shaped cutter, or roll the dough into a log for slice-and-bake cookies.