Place dough on a floured surface and dust very lightly with flour. Working the dough as little as possible, form the dough into a 14-inch log. Smooth dough with your hands to form a soft, non-sticky skin.
Sprinkle the cornmeal on a cookie sheet and place the dough cylinder on the cornmeal. Cover with a tea towel and let rest at room temperature for 40 minutes.
About 30 minutes before baking, place the broiler pan on the lower shelf and the baking stone on the middle shelf of the over. Preheat to 450°F.
Using a serrated knife make three evenly spaced diagonal slashes, about ½ inch deep across the baguette, exposing the moist dough under the surface.
Carefully place the baguette onto the center of the hot stone. Pour the hot water into the broiler pan.
Bake for 25 minutes or until the crust is a medium-dark brown and a thermometer inserted in the middle of the loaf is at least 190°F.
Remove the loaf from the oven and cool on a wire rack.