Grease a baking tray.
Sift the flour into a suitable bowl and make an indentation. Crumble in the fresh yeast and stir with a little milk, a little sugar and a little flour to form a damp. Cover and let rise for about 15 minutes.
Melt 100 g of butter. Put the remaining butter back in the fridge. Add 70 g sugar, the salt and one egg, the melted butter and the remaining milk to the dampfl and mix with all the flour to form a yeast dough. Mix the remaining sugar with the cinnamon.
Roll out the yeast dough to a thickness of one centimeter, place it on the baking tray and let it rise repeatedly for 15 minutes.
Preheat the oven to 180 °C.
Press small depressions into the dough and place the cold butter in flakes on top. Sprinkle the butter thickly with cinnamon sugar.
Bake the cake at 180 °C for about 25 minutes.
Sprinkle the still hot cake with sugar water.