Warm 125 ml milk lukewarm. Crumble yeast. Stir with 1 teaspoon of sugar and lukewarm milk until smooth. Stir in 80 g flour and dust with 20 g flour. Cover and leave to rise in a warm place for about 20 minutes until the volume has doubled. Melt 80 g butter, add 125 ml milk and warm up lukewarm.
Knead 420 g flour, butter-milk mixture, egg, 1 egg yolk, 1 pinch of salt, 40 g sugar, lemon zest and the yeast mixture with the dough hooks of the hand mixer to a smooth dough. Cover the dough and let it rise in a warm place for another 1 hour until the volume of the yeast dough has doubled. Wash the raisins and drain well. Melt 40 g butter. Roll out the dough on a floured work surface to a rectangle (50 x 30 cm) and brush with the liquid butter. Sprinkle with cinnamon and raisins. Roll the dough tightly lengthwise. Place the roll of dough in a greased springform pan ("Rein"; 24 cm Ø), forming a large dough snail. Cover and leave to rise in a warm place for about 30 minutes until the dough volume doubles. Bake Reinling in a preheated oven (electric range: 175 °C/ convection oven: 150 °C/ gas: level 2) for about 50 minutes on the lowest rack. Allow to cool in the mould and carefully remove from the mould. Dust with icing sugar.
Roll the dough tightly lengthwise. Place the roll of dough in a greased springform pan ("Rein"; 24 cm Ø), forming a large dough snail. Cover and leave to rise in a warm place for about 30 minutes until the dough volume doubles. Bake Reinling in a preheated oven (electric range: 175 °C/ convection oven: 150 °C/ gas: level 2) for about 50 minutes on the lowest rack. Allow to cool in the mould and carefully remove from the mould. Dust with icing sugar. Whisk cider, 100 g sugar and 4 egg yolks over a hot water bath for approx. 7 minutes until the volume of the cider foam has doubled. Serve immediately with the Reinling
waiting time approx. 2 hours