Basler Läckerli (also spelled Leckerli) are traditional Swiss spice biscuits or cookies with a firm and chewy texture, filled with crunchy nuts and candied citrus, and finished with a sweet glaze. They're cut into small rectangles and are popular at Christmastime but are excellent year-round.
Line a baking sheet with parchment paper and set aside.
In the bowl of an electric stand mixer fitted with the paddle attachment, add the flour, almonds, candied peels, fresh zest, cinnamon, baking powder, salt, cloves, and nutmeg. Stir on low to combine.
Add the honey and sugar to a small saucepan and heat over medium heat, stirring occasionally, until the sugar is dissolved, about 7 to 10 minutes. The mixture should be hot but not boiling. Remove from the heat and stir in the kirsch.
Pour the hot honey mixture into the mixer bowl with the flour mixture, and mix on low speed until combined (it will be fairly thick and sticky).
Scrape the dough onto the parchment paper lined baking sheet, and with a sturdy rubber spatula or the flat side of a plastic bowl scraper press and spread it into a rectangular shape measuring about 9-by-12-inches. Pat the top with wet fingers to flatten and smooth it out if necessary. Work quickly while the dough is still warm because it will be harder to shape once the dough cools.
Cover the pan with a clean dish towel and set it aside to rest for about 2 hours or up to overnight.
Dock the top of the dough with the tines of a fork, about 1 to 2 inches apart (this will help the glaze saturate the bars later).
When ready to bake, preheat the oven to 425°F (220°C) with the oven rack in the center. Bake for 15 to 18 minutes.
Meanwhile, make the glaze by whisking together the confectioners’ sugar and kirsch in a small bowl. As soon as the pan comes out of the oven, evenly brush the top of the dough slab with the glaze.
Carefully use the parchment paper to slide the baked dough (along with the parchment paper) from the hot pan onto a cutting board. The cookies are easier to cut while the baked dough is still warm, and will be more difficult to cut once it cools. While the slab is still warm, use a sharp knife to trim and remove the edges, and cut the remaining baked dough into 48 approximately 1-by-2-inch rectangular bars (cut 12 across the long edge and 4 across the short edge). Cool the cut bars completely before serving.
Notes
Store Basler Läckerli in an airtight container. They’re best after at least 1 day so they can soften and mellow a bit, but are better after even 1 week.
They will keep for up to 2 months in a sealed container at room temperature. If after a period of time the cookies harden too much, add a couple apple wedges to the sealed container (swapping out for fresh ones weekly) to re-soften the cookies.
You can use an equal total amount of mixed peel instead of separate candied orange peel and candied lemon peel (100 grams or ⅔ cup for the regular, not doubled, recipe).