Build the stiff levain and let it double-to-triple in size.
Mix all of the dough ingredients, including the ripe stiff levain, until they're incorporated.
Scrape the dough out onto a clean surface, and slap and fold the dough for about 7 minutes to develop the gluten.
Transfer the dough to a clean container, cover, and let it double in size over the next 4-6 hours. You can continue to develop the gluten with coil folding or a lamination if you wish.
Scrape out the dough onto a floured surface and preshape it into a ball. Cover and let it rest and have a final proof for about 1 hour.
Thirty minutes before the end of the final proof, begin preheating your oven to 500F with a round baking vessel inside. You can also bake the bread on a stone with a steam system or an upside-down roaster pan as a lid.
Shape your dough in the high form
Load the dough into your baking vessel and drop the temperature to 480F.
Bake 25 minutes at 480F covered and another 10-15 minutes at 450F uncovered.
The internal temperature of the bread should be over 205F when finished baking.