A Christmas tradition in Switzerland, these whimsically shaped cookies get their distinctive licorice-like flavor from whole anise seeds.
In the bowl of an electric mixer fitted with the whisk attachment, whisk eggs on medium speed until foamy. Add sugar, increase speed to high, and continue whisking until thick and glossy, about 10 minutes. Reduce speed to low and add anise seeds, kirsch, lemon zest, and salt; whisk to combine. Add flour and whisk until just combined. Divide dough into quarters, wrapping three portions individually in plastic.
Line two baking sheets with parchment paper; set aside. On a lightly floured surface, working quickly, roll unwrapped portion of dough into a rope 3/8 inch in diameter and 30 inches long. Using a sharp paring knife, cut rope into 2-inch pieces. Make three cuts on one side of each piece, being careful not to cut all the way through. Shape each piece into a crescent with the cuts on the outside of the crescent. Transfer to prepared baking sheets. Repeat process, working with one portion of remaining dough at a time, and dividing crescents evenly between baking sheets. Let stand uncovered at room temperature 24 hours.
Preheat oven to 300 degrees. Bake until set yet without any color, about 25 minutes. Transfer sheets to wire racks and let cool completely.