Mix sourdough starter and water to form a slurry.
Mix in the thick rolled oats.
Mix in the bread flour by hand (or with a Danish dough hook).
Cover and set aside for 30 minutes.
Sprinkle sea salt on top.
Fold the dough by pulling on the outside and folding over the middle so the salt is enclose.
Next, cut through the dough with two fingers to mix in the in the sea salt. Fold the dough once more and turn it over so the folds are on the bottom.
Cover and set aside for 10 minutes.
First Fold: Fold the dough again by pulling up on the outside and folding over the middle about 6-8 times.
Turn the dough over so the folds are on the bottom.
Cover and set aside for 30 minutes. Second Fold: repeat fold according to last step. Third & Fourth Fold: Repeat twice more waiting 30 minutes between folds, for a total of four folds.