Grate the carrots. Beat the eggs until foamy, add the sugar and vanilla sugar and continue to stir. Add the hazelnuts and butter and stir well. Mix flour with baking powder, sift and add with the juice. Then stir in the carrots. Butter small glasses and dust with ground hazelnuts. Pour in the batter and bake as above. For the frosting, beat the butter at room temperature until fluffy. Mix the room-warm cream cheese with the zest of the lemon and sift in the icing sugar and stir in. Work the mixture with the beaten butter into a homogeneous mass. Top the cooled cakes with the frosting and decorate as you like.