(9 x 5 inch loaf)
I baked this loaf a few days ago and it's still wonderfully moist and slightly chewy. I have been experimenting a bit with potato/flour ratios when making potato bread and love the way this particular loaf turned out.
1 medium russet potato, about 12oz
1 cup unbleached flour
1 cup whole wheat flour
1 tsp dry instant yeast
1/4 - 1/2 tsp salt, to taste
1 tbsp butter
1 cup reserved potato water
Heat up a small pot of water to a simmer.
Wash and cut the potato into a few pieces; you can leave the skin on. Drop the potato pieces into the simmering water and cook until you can pierce the pieces easily with a knife, about 10-15 minutes.
Reserve about 1 cup of the potato water and allow it to cool to room temperature. Cool the potatoes under running cold water, slip off the skin, then rice or mash them.
Add the flours, yeast, salt, butter and cooled mashed potatoes to the bowl of a stand mixer equipped with a dough hook. Set the dial to a low speed and carefully add about 1/2 cup of the cooled potato water.
Increase the speed a bit once the flour is incorporated into the dough. When the dough leaves the sides of the bowl, carefully add 1 tablespoon of potato water (with the motor on) and process until it has absorbed itself into the dough. Keep adding a tablespoon of water at a time until the dough is very moist and quite sticky, yet still leaves the sides of the bowl and clumps to the dough hook as a single ball while the motor is running. If you've added too much potato water, then add a tablespoon of flour or more, until the dough once again leaves the sides of the bowl. Work the dough with the motor running for about 8 minutes until it's smooth, moist and very tacky.
Place the dough into a greased bowl and cover it with plastic wrap. Leave at room temperature overnight.
The next morning generously grease a 9 x 5 inch loaf pan and set aside.
Sprinkle a small amount of flour over the dough and punch it down. You might have to add a bit more flour; just enough to keep your hands from sticking to it and being able to drop it into the loaf pan. The dough will be so moist that it won't really hold it's shape. Try to spread it evenly within the pan. Sprinkle a small amount of flour over the top, if desired. Cover the pan loosely and allow the dough to double it's size.
If there are one or two large bubbles near the surface, then prick those with a toothpick.
Bake loaf in a preheated 400°F oven for 10 minutes, then reduce the heat to 375°F and bake for another 25-40 minutes, or until the loaf is evenly browned and sounds hollow when you tap it.
Allow to cool completely before you cut into the loaf.