Wash the raisins, dab dry and pour rum over them. Set aside. Wash lemons and rub dry. Rub the peel off 1. Cream quark, fat, vanillin sugar, sugar, lemon peel and 1 pinch of salt for 10 minutes. Stir in the eggs one by one.
Mix flour and baking powder and stir in briefly. Grease a wreath (26 cm Ø) and dust with flour. Fill 2/3 of the dough into the mould. Mix the rest of the dough with poppy seed filling and rum raisins. Pour the poppy seed dough onto the light-coloured dough. Pull spirally through the dough with a fork. Bake in the preheated oven (electric range: 175 °C/ convection oven 150 °C/ gas: level 2) for 50-60 minutes. Leave to rest in the pan for 5 minutes. Remove from the mould and allow to cool. Meanwhile, remove the zest of the 2nd lemon in strips using a zest ripper. Set aside. Cut 1 lemon in half, squeeze the juice and stir with icing sugar until smooth.
Leave to rest in the pan for 5 minutes. Remove from the mould and allow to cool. Meanwhile, remove the zest of the 2nd lemon in strips using a zest ripper. Set aside. Cut 1 lemon in half, squeeze the juice and stir with icing sugar until smooth. Pour the icing over the cooled down cake. Sprinkle with sugar crystals. Arrange the cake on a plate and decorate with lemon peel strips