To the approximately 200 g of preferment add:
450 - 500 g water, non-chlorinated, 70- 85F (depends on how stiff the preferment is and how hydrated you want your final dough)
800 g Heritage White or Bread Blend Flour or Pizza Flour
1 Tbsp sea salt scattered onto the flour. (a salt with a high mineral content is best)
Mix thoroughly - this can be done with a stand mixer or by hand in a bowl. It can be a bit messy. Wetting your hands a couple of times while mixing helps (flouring your hands can add too much flour to the dough). This mixing requires squeezing and turning the dough until all the ingredients are combined.
Let it rest for 45 minutes
Scrape the dough out on a clean surface. Wet your hands and stretch and fold 5-10 times letting it rest a few minutes between stretches. You should feel the dough developing strength.
Divide into two equal portions. Round each portion into a ball and drag each on a dry surface to create surface tension.