2 egg whites 2½ cups confectioners' sugar 1 tbsp. ground cinnamon 1 tbsp. kirsch (cherry brandy) 2½ cups blanched whole almonds 1 cup sugar, plus more for rolling cookies ¼ cup rum
1. Whisk egg whites in a bowl to stiff peaks. Whisk in confectioners' sugar to make glaze; pour off ⅔ cup and reserve. Add cinnamon and kirsch to remaining glaze; set aside. Finely grind almonds in a food processor; add granulated sugar and finely grind. Transfer to bowl with spiced glaze; mix into dough.
2. Transfer dough to a surface sprinkled heavily with sugar; cover with parchment paper. Roll dough until ¼" thick. Uncover and spread reserved glaze over dough; let sit until glaze sets, about 30 minutes.
3. Place rum in a bowl, and using a 1¾" star cutter, dip cutter in rum and cut out a cookie; repeat and transfer to parchment paper-lined baking sheets, spaced 2" apart. Let dry for 3 hours. Heat oven to 450°. Bake cookies until glaze just sets but does not brown, 3–4 minutes.