Bring the milk to the boil. Grate the potato and add it to the milk. Leave to cool until lukewarm.
Add the dried yeast to the sieved flour and salt and stir in the potato/milk mixture. Add the egg and buttermilk and knead well. Put in a covered bowl in a warm place to rise for 2–2½ hours. Knead again and divide between three well-greased bread tins. Leave to rise again for about 40 minutes and then bake at