4 ounces of barm
4.5 ounces unbleached high gluten or bread flour
1 to 2 ounces of water

Remove the barm from the refrigerator and measure it out one hour before starting to take off the chill. Dip a measuring cup into water then scoop the barm so it won't stick.

Add the flour to the barm adding only enough water so that you can knead this inot a small ball. You don't need to work it very long, just until the flour is hydrated and the barm evenly distributed. Lightly oil a small bowl, place the starter in and turn to coat with the oil. Cover and ferment for ~4 hours or until double. Once it is double in size put in the refrigerator overnight.

On the second day remove the starter from the fridge one hour before using it. Cut it into 10 pieces with a pastry scraper or a serrated knife. Mist with spray oil, cover with a towel and let it sit for one hour to take off the chill.

To make the dough:

20 ounces flour
2 teaspoons salt
12 to 14 ounces of water
Semolina flour for dusting - optional but tasty.

Stir together the flour and salt in a 4 quart bowl. Add the 10 starter pieces and enough water to bring every thing together into a ball. Sprinkle the counter with flour and transfer the dough. Knead for 12 to 15 minutes. The dough should be firm but tacky and should be between 77 and 81 degrees. Lightly oil a large bowl and roll the dough around in it to coat. Cover with plastic wrap.

Ferment for 3 to 4 hours until it has doubled in size.

Gently remove from the bowl and divide into to equal halves being careful to degas as little as possible. Gently shape the dough into boules.

Proof the dough on parchment lined sheet pans that have been dusted with semolina flour or cornmeal. Mist with spray oil and loosely cover the dough with a towel or plastic wrap.

Proof the dough for 2 to 3 hours and bake in a very hot oven, 500 degrees with a steam pan on the lowest rack. As you place the dough in the oven put in 1 cup of water into the hot steam pan. Then lower the oven to 450 degrees. Bake for 20 to 30 minutes or until the center registers 250 degrees with a thermometer.

Cool for 45 minutes before slicing.