01 - Combine flour and water in a large bowl until just incorporated. Cover and rest for 30 to 45 minutes.
02 - Add the sourdough starter and salt to the dough. Mix thoroughly until a shaggy mass forms.
03 - Turn dough onto a lightly floured surface and knead or perform stretch-and-folds for 5 to 8 minutes until smooth and elastic.
04 - Place dough in a lightly oiled bowl, cover, and let it rise at room temperature for 4 to 6 hours, performing stretch-and-folds every 30 minutes during the first 2 hours.
05 - Turn the dough out and divide into two equal portions. Shape each into a tight round loaf.
06 - Place rounds seam-side up into floured proofing baskets or bowls. Cover and refrigerate 4 to 8 hours or let rise at room temperature until puffy, about 1 to 2 hours.
07 - Preheat oven to 450°F with a Dutch oven or baking stone inside.
08 - Turn each loaf onto parchment paper, score the tops, and transfer carefully to the hot Dutch oven or stone. Bake covered for 20 minutes, then uncovered for 20 minutes until deep golden brown.
09 - Cool loaves completely on a wire rack before serving.
10 - Slice the tops off each loaf and hollow out the center, leaving a ¾ to 1¼ inch wall for a bread bowl. Fill with desired soup, stew, or dip.