Whisk the sourdough starter into warm water until fully combined. Add the flour and salt, mixing until a shaggy dough forms.Cover and let rest for one hour. Perform four sets of stretch and folds, spaced about 30 minutes apart.
Allow the dough to rise at room temperature until it has increased by about 50–60%. It should look slightly puffy and have small bubbles visible beneath the surface.This typically takes about 4–6 hours, depending on your kitchen temperature. Turn the dough out onto a clean surface and gently stretch it into a rectangle.Spread a layer of chili oil crunch over the dough and sprinkle with green onions and shredded cheddar(if using). Fold one side of the dough inward, then repeat with another layer of filling. Fold the opposite side over the top and add a final light layer.Roll the dough up into itself to form a loaf. Then gently shape it into your desired form, building surface tension without pressing out the layers. Place the dough seam-side up into a floured proofing basket or a towel-lined bowl. Cover and refrigerate for 12–15 hours.
Preheat your oven to 450°F (230°C) with a Dutch oven inside.Turn the dough out onto parchment paper, flour, score the top, and transfer it into the hot Dutch oven.Bake covered for 25 minutes, then uncover lower temperature to 425℉ and bake for another 20 minutes until deeply golden. Allow the loaf to cool for at least 1 hour before slicing.
