Mix the water, yeast, and flour. Cover with plastic wrap and let rise at least 8 hours, and preferably overnight.

Add the water, sugar, salt, and yeast to the bowl of a stand mixer. Add the sponge and mix with the dough hook until incorporated.

Add the flour, by tablespoon, until you have a cohesive dough. I used about 2.8 ounces.

Mix with the dough hook for 15 minutes on low until smooth and elastic.

Divide the dough into 4 equal pieces. Roll each piece out into a 10 inch by 10 inch square. Roll the dough into a log, tapering the ends and pinching the seam closed. Place the logs onto a parchment lined baking sheet or pizza peel and cover loosely with oiled plastic wrap. Let rise until doubled, approximately 60 to 90 minutes.

One hour before baking, preheat the oven to 500 degrees F with a baking stone (if you have one) on the middle rack and a broiler pan on the bottom rack. Fill a spray bottle with water.

When the bread has doubled in size, lightly slash the loaves down the center with a very sharp knife or a lame. Place two cups of boiling water into the broiler pan, and slide the loaves, parchment and all, onto the pizza stone. If you dont have a pizza stone, place the baking sheet with the loaves on the middle rack. Spray the sides of the oven with water and close the door. Reduce the oven heat to 450 degrees F.

Spray the oven with water 3 more times during the first 10 minutes of baking with water. Bake the loaves for a total of 20 to 25 minutes, until lightly golden brown. Cool on a wire rack.