1. Combine 1 cup (250ml) of water, 1/2 cup (120g) of sourdough starter, and 3 1/2 cups (420g) of all-purpose flour in a large bowl. Mix the ingredients together until a shaggy dough forms. Cover the bowl with a lid or plastic wrap and let it rest for 1 hour at room temperature.

2. Add 1 teaspoon of salt to the dough. Wet your hands and knead the salt into the dough until it's fully dissolved. Transfer the dough to a lightly oiled bowl, cover it with a lid, and let it rest for 30 minutes.

3. Fold the dough four times, with 30-minute intervals between each fold. To fold the dough, use your hands to gently lift and fold the edges towards the center. After the fourth fold, let the dough rest for 1 hour.

4. Gently shape the dough into a tight ball and place it on a lightly floured surface. Let it rest for 20-30 minutes.

5. Prepare a round basket or bowl by placing a kitchen towel inside and lightly flouring it. Sprinkle some flour over the dough and use a dough scraper to gently turn it over. Fold the dough into a package by grabbing the opposite sides and meeting them in the middle. Repeat with the other two sides, then turn the dough over and shape it into a round loaf. Tuck the edges under the loaf.

6. Transfer the dough to the floured basket using a dough scraper. Smooth the top of the dough and fold the towel over it like a package. Let it rise for about 1 hour at room temperature.

7. Place the basket in the refrigerator and let the dough chill for at least 12 hours or overnight.

8. The next day, preheat your oven to 482°F (250°C) with a baking stone or baking steel inside. If you have a steam function, use it. Otherwise, place a pot of boiling water in the oven.

9. Remove the dough from the refrigerator, turn it over onto a parchment-lined baking sheet, and sprinkle with flour. Use a sharp knife or razor blade to score the dough immediately, then bake.

10. After 10 minutes, lower the oven temperature to 392°F (200°C). After another 10 minutes, open the oven door to release the steam and remove the pot of water. Continue baking until the bread is golden brown and sounds hollow when tapped, about 10 more minutes. Use a thermometer to check the internal temperature, which should be around 203°F (96°C) for light bread.

11. Remove the bread from the oven and let it rest for 1 hour before slicing. This will help the bread retain its moisture and make it easier to slice.