Gently boil potatoes in water until tender. Once cooked, drain reserved potato water. Mash potatoes and allow to cool.
Once the potato water is tepid, add yeast to some of the water to dissolve. Add malt extract. When combined add to mashed potatoes and stir gently to combine.
Sift flour and salt into a large bowl, then add the mash mixture. Add enough water to mix to a soft dough. Once the dough has come together, tip out onto a floured surface and knead for 10-15 minutes. This can be mixed in a kitchen aid using the dough hook attachment for roughly 5 minutes or until the dough is soft, elastic and shiny.
Cover dough and rest until doubled in size. Once the dough has proved, knock back dough and shape into 3 loaves. Place loaves onto baking sheets that have been greased and lined with baking paper. The bread can also be placed in loaf tins if desired. Allow dough to prove again on baking sheets until it has doubled in size. Preheat oven to 200 degrees Celsius.
Dust loaves with a light coat of flour, place in the oven turning down the heat to 190 degrees and bake for 25-35 minutes or until golden. The bread should sound hollow when tapped.