Add 350g room temperature water to a small bowl, add starter from the night before and mix till mostly homogeneous.
Add water/starter mixture to the flour and stir just till flour is incorporated. Cover and let rest for 25 minutes at room temperature.
Mix 20g salt, 30g water, and 1g barley malt (optional) in a small bowl (it will not fully dissolve) Begin kneading the dough, folding and working in the salt slurry small amounts at a time till fully incorporated. This should take 5-10 minutes. This is a good time to re-weigh your dough and divide the weight by 4 to get your exact dough ball size. Cover and let rest at room temperature for 25 minutes.
Working in small amounts knead and fold 10g olive oil into the dough until fully incorporated and smooth. Cover and bulk ferment at room temperature for 2-3 hours. Lightly flour a work surface. With floured hands remove the dough from the bowl. Lightly dust with flour. Divide into 4 equal portions. Form the dough balls making sure the balls are fully closed.
Lightly oil a dough tray, individual bowls, or plate. Place lightly floured dough ball inside, cover tightly, and let ferment at room temperature for 2-4 hours till nicely proofed (they should increase in size with small bubbles present).
After the room temperature fermentation place inside the refrigerator and cold ferment for 24-72 hours. (Alternatively the dough may be used immediately after the initial room temperature fermentation)