Crumble the yeast and dissolve in 70 ml lukewarm water with a pinch of sugar.
Place 250 g of flour in a suitable bowl and press an indentation in the center.
Add the yeast and another 100 ml of lukewarm water. Stir to a thick paste. Cover and let rise for at least 2 hours (preferably overnight).
Knead in salt and the remaining flour with your hands. Let rise for another half hour. Shape the dough into an oblong loaf.
Put it on a greased baking tray and let it rise for another 15 minutes. Preheat the oven to 200 °C and bake the bread for 1 hour.