Mix flour, sugar, vanillin sugar and salt in a mixing bowl, press a depression in the middle. Warm 200 ml milk lukewarm. Dissolve yeast in 100 ml milk. Pour the yeast milk into the flour bowl, mix with some flour from the rim and let it stand covered for about 15 minutes
Add the egg, 100 ml lukewarm milk and butter and knead to a smooth dough using the dough hooks of the hand mixer. Cover and leave to rise in a warm place for about 45 minutes
Chop pistachios, almonds and walnuts. Bring cream and honey to the boil, add nut mixture, up to about 50 g, and simmer for about 2 minutes. Remove the pan from the heat and let it cool down. Grease a box cake tin (11 x 30 cm, 7 cm high)
Briefly knead the dough and roll out on a floured work surface to form a rectangular plate (approx. 35 x 40 cm). Spread the nut mixture evenly on top, leaving an approx. 1 cm wide rim all around. Roll up the dough sheet firmly from the short side. If necessary, slightly compress the ends. Carefully place the roll of dough in the tin. Cover and leave to rise in a warm place for approx. 30 minutes
Bake in a preheated oven (electric cooker: 175 °C/ convection oven: 150 °C/ gas: see manufacturer) for approx. 45 minutes. If necessary, cover with aluminium foil at the end. Let the cake cool down in the tin for about 30 minutes. Then remove from the tin and let it cool down on a cake rack for 2-3 hours
Mix 1 tablespoon milk and icing sugar until smooth. Decorate the cake with icing and the remaining nuts
waiting time 4-5 hours