Springerle are German cookies that date from sometime around the 1500s, give or take a century. I will note that this is long before artificial refrigeration became a thing in the mid-1700s, which accounts for some of the strange tactics that I'm about to describe. The name springerle translates to "little jumper" or "little knight" - it's unknown precisely why they bear this name, but the earliest molds that have been discovered frequently depict horses, and the dough rises substantially when it's baked (it gets "feet" - like macarons, only much larger). The dough is made without refrigeration, and it's packed into intricately-detailed molds. Springerle were popular back in their day for many religious celebrations, but in recent times, like many other cookies, they have become a tradition for the winter holidays.
So why do I think this cookie is weird? Well, for starters, after you make the dough and shape the cookies in the molds, you leave the cookies to dry for 24-48 hours. The only step where you need to move quickly is between finishing the kneading of the dough and getting it into the mold. The reason is that this dough very quickly develops a thin crust that will crack if you disturb it in the slightest way. So you take the dough, roll it, stamp it with the mold, transfer them somewhere where they won't be in the way for a few days, and leave them to dry out. That way, when you finally bake them, the beautifully-molded print stays exactly in place without expanding. The reason you get the "feet" at the bottom is that the dried surface means that the only direction the dough can expand while it's baking is...down!
The next weird thing about springerle is the actual preparation of the recipe. The first step in the recipe is "Beat eggs until thick and lemon-colored (10-20 minutes)." Let me repeat that: Beat the eggs for TEN TO TWENTY MINUTES! I have a Professional series KitchenAid (a same-day purchase a few years back when my Artisan died a loud and smoky death when tripling the Chocolate Dreams recipe proved to be too much "flour power" for it to handle), but this recipe causes the motor section to get uncomfortably hot after being on for so long. It's actually quite an impressive feat to do this to eggs, especially when you remember that this recipe is from the 1500s!! If you've ever tried to churn your own butter or make ice cream by hand, you'll understand how utterly exhausting a task this would be without an electric mixer.
Ok, so the eggs are finally thick and lemon-colored. What's next? The ingredient list is quite short, but the three main ingredients (in massive quantities) are eggs, powdered sugar, and fine cake flour. There are also a few other ingredients in relatively miniscule amounts (butter, baking powder, salt, and whatever your flavoring is - mine use anise). After adding everything but the flour, you once again mix it...for FORTY minutes! That's 40 - four-zero - MINUTES. My KitchenAid, at this point, is steaming hot and protesting loudly.
Another strange fact is that the recipe doesn't actually call for baking powder. Instead, it calls for hartshorn. Hartshorn (also known as baker's ammonia) is, as it sounds, made from deer antlers, and it was popular in the 17th & 18th centuries as a leavening agent in cookies and other baked goods. It also helps the designs in cookies like springerle to retain their shape, and it makes baked goods last a bit longer. Unfortunately, when baked, hartshorn also releases ammonia gas, which can combine with molecules in other common ingredients to form a carcinogen - so if you see a recipe that calls for hartshorn, go ahead and substitute baking powder instead (at the ratio of 1/2 tsp hartshorn to 1 tsp baking powder).
Finally, springerle recipes often note that these cookies are best after 3-4 weeks! Most cookie recipes read like a race against the clock: "Don't turn your back, or they'll burn!" "Work quickly or the heat from your hands will..." "If you're making these during the summer, you may need to work extra quickly..." "Best if eaten within 48 hours." Well, not springerle - springerle are apparently at their peak once they've aged a bit (and become rock-hard), so you can take your sweet time!
