Making the Cookies
1. Preheat the oven to 350 degrees F. Line 3 baking sheets with parchment paper or grease with neutral-flavored oil.
2. Spread the hazelnuts on a baking sheet and toast in the oven for about 10 minutes, or until you start to smell them. Be careful not to let them burn. Immediately remove them from the oven and spread on a clean kitchen towel. Wrap the four corners of the towel over the top and let sit for a few minutes — the steam will help loosen the nut skins. Roll the nuts around in the towel— most of the nuts will become skinless. Coarsely chop and set aside.
3. In a large bowl, whisk together the eggs and granulated sugar until light and foamy.
4. In a separate bowl, sift together the flour, baking powder, spices and cocoa. Stir the dry ingredients into the egg and sugar mixture. Add the brandy and the nuts and stir to combine.
5. Drop by teaspoonfuls or tablespoonfuls onto the prepared baking sheets, 2 inches apart. Bake for 10 to 15 minutes, or until lightly browned. Remove from the oven and place on a rack to cool.
Making the Glaze
6. Combine the confectioners’ sugar and lemon juice in a small bowl and stir until smooth. Add a drop of water if the glaze is too thick.
7. While the cookies are still warm, drizzle each one with a small spoonful of glaze. Let cool.
Excerpted from “The German-Jewish Cookbook: Recipes and History of a Cuisine” by Gabrielle Rossmer Gropman and Sonya Gropman (Brandeis University Press).