Make sure your starter is recently fed and very active A dollop of starter should float in a glass of water, if it sinks it isn't strong enough yet

Using a food scale to measure the ingredients by weight will give you the most accurate results Set a large bowl on the scale and zero it out

To the bowl with the scale zeroed out add 525 grams water  (80 degrees F) be careful that it doesn't contain chlorine Then add 250 grams of your very active starter

Mix the starter and water thoroughly with a whisk or by hand, then add 700 grams white whole wheat bread flour Mix with the dough bowl scraper, then use wet hands to form a shaggy dough ball

Let it rest (autolyse stage) about an hour  This stage can be extended without worry up to four hours at 75 degrees F After autolyse, add  20 grams sea salt salt to the bread dough  Use your hands to pinch and stretch the dough gently until the salt is mixed into the dough

Using your wet hands pull the dough from under the dough ball up and stretch it gently as you pull it over the dough ball top Repeat this process as you give the bowl quarter turns until the dough is stretched and pulled from each quarter of the bowl Over the next 2 1/2 hours repeat the stretch and fold every 30 minutes

Allow the dough to bulk rise in the bowl at room temperature an hour or so until it rises by roughly 30 percent Cover the bowl of dough with a plastic bag and set it in the fridge for 15 to 18 hours This is the long cold rise

After the cold rise is complete, remove the dough from the fridge and let it sit on the counter in the bowl for two hours or until the dough reaches room temperature On a clean un-floured counter pour out the dough into a large mass  Flour the top of the dough lightly but evenly

Divide the dough mass in half with your metal dough scraper Form each half into a dough ball turning and rotating to create internal tension Let the dough balls rest for 30 minutes or so

Place each dough ball seam side up in a rice floured, cloth lined banneton or bowl Rise in the fridge 2 to 4 hours until completely chilled

Set your dutch oven with its lid on the lower third of oven Preheat the oven to 450 degrees F. to warm the dutch oven Remove the dough from the fridge and turn it upside down onto a large piece of parchment paper

Score the loaf with your lame knife or a razor blade Carefully lift the parchment paper with the loaf into the hot dutch oven Put the lid on the dutch oven and return it covered to your preheated oven Bake for 30 minutes

Remove the lid of the dutch oven after 30 minutes  Bake an additional 10 minutes uncovered or until the loaf thumps hollowly and the surface gets dark Allow the bread to cool for at least 1 hour before cutting