For the nut gingerbread cake, first separate the eggs. Beat egg whites with a pinch of salt until stiff. Beat egg yolks, sugar and vanilla sugar until foamy.
Mix honey gingerbread spice, 1 strong shot of rum, grated nuts, yogurt and chestnut flour into the yolk mixture. Fold in beaten egg whites and bake in a greased and floured springform pan (diameter 20 cm) at approx. 170 °C. Allow to cool.
Cut the cake in half, spread with Powidl and put the upper part back on top. Brush the cake with honey and sprinkle with grated nuts.