Peel, wash and halve the potatoes and cook in boiling salted water for about 20 minutes. Drain, let it evaporate briefly and mash it finely with a potato masher. Let cool down lukewarm
Stir sugar beet syrup, sourdough and yeast until smooth. Knead 600 ml lukewarm water, potatoes, 400 g wheat flour, rye flour and 4 teaspoons salt to a smooth dough (dough is very sticky.) Pour dough into a bowl twice as big, close tightly with foil and leave to rise in the fridge overnight
Knead 200 g wheat flour and fried onions into the soft dough. Divide the dough into thirds and form 3 long loaves of bread. Roll each in oat flakes, sunflower seeds or pumpkin seeds. Turn the loaves onto a baking tray lined with baking paper. Cut the surface several times, cover and leave to rise in a warm place for about 1 hour
Bake in the preheated oven (electric cooker: 225 °C/ convection oven: 200 °C/ gas: see manufacturer) for approx. 20 minutes. Let them cool down
waiting time approx. 13 hours