Start by pouring water into a large glass bowl and adding the crucial starter. Mix until it completely dissolves. Then, add salt and flour, and mix with your hands until the flour almost mixes in and becomes shaggy. Cover the bowl with a clean kitchen towel and leave it for 1 hour.
After an hour, gently and thoroughly fold the dough four times using hands dipped in cold water. Cover the bowl with a kitchen towel and leave it to rest for 20 minutes. You can repeat the folding process twice or three more during this time.
After a final stretch, shape the dough into a ball, cover it with a kitchen towel, and leave it to rise for 8 to 12 hours. Patience is key here, as this time allows the dough to develop the desired spring-like texture and bounce back when your finger is inserted.
Once the dough is ready, please remove it from the bowl and place it on the counter. Put a little flour on top of the dough and turn it over. Pinch the edges and bring them to the center like a tied-up sack.
Turn the dough upside down on the counter so the seams face down. Use your hands to gently pull the dough towards you and shape it into a ball by rotating it. Make sure to tighten the edges all around. Sprinkle a little flour on it.
Put a kitchen towel in a bowl or colander and sprinkle flour. Use a dough scraper to pick up the dough and turn it over onto the towel. Cover it and let it rise at room temperature for 30 minutes. After 30 minutes, place the dough in the refrigerator for at least 1 hour.