Combine the active starter with water in a mixing bowl.
Mix well until it reaches the desired consistency.
Add the all-purpose flour.
Mix until combined, which should take a few minutes.
Add sea salt, along with the rest of the water.
Cover with foil and let it rest for half an hour.
When the dough is ready, knead it for a few minutes, to incorporate the salt and water.
Cover and let it sit for another half hour.
Do this again a few more times, allowing the dough to rest for half an hour each time.
After the fourth or fifth time, cover it again and let it rest at room temperature until the dough doubles in size.
Transferring the dough onto a counter, and cutting it in half.
Give the dough a square shape, and roll it up.
Push the rolled dough first, then follow by pulling it towards yourself, giving tension.
Do this last step a few more times until the dough is bouncy enough.
Do the same with the other half.
Let the two halves rest for half an hour, uncovered.
After half an hour, do the push-pull step once again, with both halves.
Carefully place the loaves into two different baskets and cover them with plastic.
Transfer the baskets to the fridge and cool them for two hours.
Gently place the loaves in the oven, ideally in an iron pot.
Cover and bake for half an hour at 450 degrees.
Remove from the heat and let the dough cool before serving.