If you use homemade sourdough, it has to be fed first and should rest for 16-20 hours. If you use purchased sourdough, you can skip this step and start preparing the dough straight away.
To do this, put the lukewarm buttermilk with the yeast in a mixing bowl and stir until the yeast has dissolved. Then the sourdough is added and is also stirred. Now the two types of flour are added and finally the salt. The dough is kneaded for 8 minutes (4 minutes on the smallest and 4 minutes on the next higher level) with the dough hook of the food processor. If you don`t have a food processor, knead the dough with your hands right from the start. If the dough is very sticky and does not come off the edge of the bowl after 4 - 5 minutes, just add flour until the dough comes off the edge of the bowl (this can vary greatly depending on the buttermilk brand).
The dough is knitted in a round shape on a lightly floured work surface and then placed in a floured bowl or proving basket with the closure facing down and has to rise in a warm place for 60 - 90 minutes.
After this rising time, the dough piece is placed with the lid on top in an ovenproof dish with a lid and must be baked in a preheated oven at 220 ° C top / bottom heat for 50 minutes with the lid, then a few more minutes (under observation) without the lid, so that it can still tan.
The bread should now cool down on a cooling rack before it can be consumed. Lukewarm and consumed on the same day is an absolute highlight, but it can of course also be stored in suitable containers.