Deservedly one of the most popular German Christmas cookies. The dough is very fragile and sticky, but the results will make your perseverance worthwhile. If desired, the dough can also be shaped into 1-inch balls and flattened slightly.

Preheat the oven to 300°F. Grease or line 2 baking sheets or cookie sheets with parchment paper.

Whip to medium-firm peaks in a large bowl:

Gradually beat in:

Beat until stiff and glossy. Transfer one-third of the egg white mixture to another bowl and set aside. Fold into the remainder:

Dust a work surface lightly with powdered sugar. Pat the dough out to a thickness of ⅓ inch; it is too delicate to roll. If it sticks, dust your palms with powdered sugar. Cut using a 1 ½-inch star cutter. Arrange on the prepared baking sheets about 1 ½ inches apart. Brush the tops with the reserved egg white mixture. Bake until the tops look dry and slightly crackled, about 20 minutes, switching oven racks and rotating the sheets halfway through. Let cool on the sheets for 2 to 3 minutes, then transfer to a wire rack to cool completely.