1. Boil the potatoes (skin on) in some salted water until done, drain, peel, and weigh about 7 oz. (200g) into a bowl. Mash with a potato masher while still warm and then let cool down.

2. Crumble the yeast and mix it with the lukewarm water – let it stand for about 5 minutes so the yeast can bubble up a bit. Mix the flour with the salt in a large bowl, add the yeast water and knead for about 2 minutes to form a smooth dough. Add the mashed potatoes and knead for another 3-4 minutes. Cover the bowl with a clean kitchen towel and let the dough rise at room temperature for about 4 hours.

3. Grease a loaf tin lightly. Knock the air out of the dough, shape it into a loaf, and place it inside the loaf tin. Brush the dough with some water, cover, and let rise another 20 minutes. Meanwhile, preheat the oven to 480°F (250°C). Place a heatproof bowl with water on the bottom of the oven. Make several cuts in the risen dough with a very sharp knife and place the tin in the center of the oven. Reduce the temperature to 450°F (230°C) and bake the bread for about 45-50 minutes. Check after 30 minutes, if the surface gets too dark, cover with aluminum foil and continue baking. Take the finished bread out of the oven, remove it from the pan and let cool on a wire rack.