Potato water is a great addition to bread – the potato starch in the water helps bind moisture to the bread, gininv you a longer shelf life and a moister crumb. I always save the water from boiled potatoes and cool for use in bread. So next time you make mashed potatoes, don’t throw out the drained water – save it for your bread. (or your gravy – there are vitamins and minerals in that water).
By the same token, I save the water from my cooked vegies for vegetable stock.