Hazelnut Cookies with Cinnamon

For the dough, place the powdered sugar in a bowl. Beat egg whites with the lemon juice until stiff. Gradually add the powdered sugar and beat until shiny and stiff. Then stir in vanilla, cinnamon, baking powder and 10 1/2 ounces nuts. Mix with hands into a smooth dough that no longer sticks to your hands.

Scatter remaining nuts over lightly floured work surface. Roll out the dough approximately 1/4-inch thick over the nuts. With floured cookie cutters, cut out as desired into star and letter shapes. Place on a baking sheet lined with parchment paper .

For the topping, beat egg whites with lemon juice until stiff. Sprinkle in powdered sugar and stir into a thick icing. Spread over the cut-out cookies and allow to dry overnight.

Preheat the oven to 120°C / 250°F convection (or 275˚F non-convection)

Bake about 15 minutes. Do not overbake, as the icing should remain white.