Combine the water, yeast, and salt in a 5 quart bowl. Stir to mix. Add all of the flour at once and mix with a spoon until the dough is wet and sticky with no dry patches. This is easy to do by hand, but I usually do it in my stand mixer.Cover loosely with plastic wrap, or a dish towel. Let it rise for about 2 hours at room temperature. If you are not using it immediately, refrigerate the dough, loosely covered, for up to a week.
To make a loaf, sprinkle some flour onto the surface of the dough. Divide the dough in half and rub with a layer of flour while gently stretching the top around to tuck the sides into the bottom to form a round, smooth loaf. Repeat with the second half of dough to form another loaf.Place loaves on a board or pan dusted with cornmeal or flour to prevent sticking. Let them rise, uncovered, for at least a half hour or as long as 90 minutes. The loaves will plump, but not change drastically in size.
About 20 minutes before baking, preheat the oven to 450°F. Place a sheet pan cake pan on the bottom rack of the oven. Put the baking stone on the middle rack.
Dust the loaves liberally with flour. Slash the tops with a cross or three lines with a sharp knife and slide them onto the preheated baking stone. Carefully pour about 1 cup of hot water into the lower pan and close the oven door to trap the steam. Bake for about 25 minutes, until the crust is browned and the loaves feels light and hollow.
Cool for a few minutes on a wire rack before slicing. We like to serve it warm, but it reheats well, too, so can be made ahead for convenience.