To make the cinnamon balls, toast the hazelnuts in a pan or in the oven. Put them on a dish and rub them a bit so that the brown skin comes off. Then grate finely.
Beat the egg whites until stiff, add vanilla sugar and sugar and beat until very stiff. Take 3-4 tablespoons of this mixture. Fold the cinnamon and the grated nuts into the rest.
Form walnut-sized balls, brush with a little egg white mixture and decorate each with a hazelnut. Bake the cinnamon balls at 120°C for about 30 – 35 minutes.