Cooking
Generously grease the 2 parts of the mould with a butter-flour mixture (made beforehand, e.g. 100 g of butter and 50 g of flour). Close the 2 parts of the Lammela mold with the hook. Pour the cookie dough into the pan. Bake at 170°C for about 35 to 40 minutes.
Using the tip of a knife, check for doneness. The blade should come out dry, if not, let cook for a few more minutes while checking the cooking.
After cooling and before serving, sprinkle with powdered sugar.