Boil the potatoes, uncovered, in salted water for approx. 40 mins. until soft. Drain the potatoes, cut into chunks, push through a sieve, mix in the butter.
Mix the flour, salt, caraway seeds and yeast in a bowl. Mix in the water, maple syrup and potatoes, knead to form a soft dough. Cover the dough and leave to rise at room temperature for approx. 2 hrs.
Place the casserole dish (incl. lid) in the lower half of the oven. Preheat the oven to 240°C.
Remove the casserole dish, put the baking paper and dough in immediately. Make diamond-shaped incisions in the surface. Cover and bake for approx. 30 mins. Remove the lid and cook for a further 20 mins. Remove the bread from the dish, leave to cool on a rack.