In large bowl, whisk together dry ingredients. In separate container, mix together wet ingredients. Add wet mixture to dry mixture and use a spatula or your hands to mix until all flour is incorporated.

Cover bowl in plastic wrap and set aside to rest 30 minutes.

Grab top edge of dough with oiled hands, stretch it upward and fold over to other side. Turn bowl 90 degrees and repeat stretching and folding 12 times. Let dough rest another 30 minutes.

Repeat stretch and fold process. Turn dough over, seam side down. Sit covered at room temperature overnight, at least 8 hours.

First rise: Dust dough with flour. Place spatula between dough and bowl, turn bowl upside down, and place dough on a floured work surface. Flour your hands really well and hold bottom of dough. Pull/spread in all four directions to form a square. Fold top and bottom in thirds onto itself and fold left and right sides in thirds onto itself as well. Turn it over and pull it toward you several times to stretch the surface. Cover with a bowl and leave on work surface to rest 20 minutes.

Second rise: Dust surface with flour. Press dough gently to flatten then turn it over. Fold dough toward center, pulling each corner in turn, until dough becomes taut. Turn it over and pull toward you several times to stretch surface. Place on parchment paper. Cover with a bowl and let sit about 1 hour.

Preheat oven to 450 degrees F. Place cast iron pot (or heavy cooking pot) in oven with a lid.

If desired, sprinkle dough with sesame seeds and cut a slit on top. Add parchment paper to preheated pot, place dough in pot and bake covered 30 minutes, then uncovered 10 minutes.

Transfer bread to wire rack and let cool completely before slicing.