Mix the Sourdough, Then Stretch and Fold

I'm following Modern Eats Farmhouse Easy Sourdough Bread Recipe. Click through to get the whole recipe and lots of good info. 

MIX the SOURDOUGH

MIX together 100 grams of sourdough starter and 375 grams water.

NOTE: The sourdough starter should have been taken out of the fridge and fed the day before. See: Feeding your sourdough starter. 

Then ADD 500 grams bread flour and 12 grams salt

COVER with a damp towel and let rest for 30 minutes.

Pictured: Mixed Dough

Stretch and Fold

Pictured: First Stretch

From Modern Eats Farmhouse Easy Sourdough Bread Recipe: 

 "Grab underneath one side of the dough and pull straight up to stretch the dough without breaking it, then fold over the center. Give the bowl a quarter turn then repeat again with the next side. Repeat this process until you've stretched and folded all 4 sides of the dough (think North, South, East, West). Cover with a (damp) towel and let rest. Repeat this stretch and fold process every 30 minutes over 2 hours, for a total of 4 times."

Pictured: Second Stretch

Pictured: Third Stretch. Smoother.

Pictured: Fourth Stretch. The Smoothest!

Pictured: Bulk Fermentation (First Rise). 

Covered with plastic wrap.

Pictured: Then covered with a towel.

Now we wait 8-12 hours. 

Shaping is next...