Dissolve the yeast in milk and water. Knead with the other ingredients for the dough to form a homogeneous dough and cover it and let it rise for about three quarters of an hour in a warm place (e.g. a heater) until the dough has about twice its volume.
Preheat the oven to 175 ° C top and bottom heat. Pinch some baking paper between the base and ring of a 26-inch springform pan and grease the edge well with butter.
For the topping, mix the cinnamon and the white and brown sugar in a small bowl with enough melted butter so that the mixture spreads well but doesn`t run away.
Roll out the dough on a floured surface 0.5-1.0cm thick and as rectangular as possible. Spread the cinnamon mixture evenly on top and then roll up the dough from the longer side. Use a smooth, sharp knife to cut the rolling pin into 4 cm wide pieces and place them side by side in the springform pan. Leave a little space towards the edge, they will open really nicely.
Bake the Kanebullar cake for about 30 minutes.
In the meantime, prepare a frosting from powdered sugar, vanilla sugar and some whole milk. Spread this generously over the hot cake immediately after baking.