In a large bowl, combine the sourdough starter and warm water. Stir to combine.
Add the bread flour and salt. Use a wooden spoon or your hands to mix the ingredients until a shaggy dough forms.
Turn the dough out onto a lightly floured surface and knead for 5-10 minutes, until the dough becomes smooth and elastic.
Place the dough in a lightly greased bowl, cover, and let rise for 8-12 hours at room temperature, or until doubled in size.
Punch down the dough to release any air bubbles. Shape the dough into a round loaf and place it in a parchment-lined or greased 9-inch round baking pan.
Cover the dough and let it rise for another 1-2 hours, until it has puffed up slightly.
Preheat your oven to 450°F (230°C).
Bake the bread for 20 minutes, then reduce the temperature to 400°F (200°C) and bake for an additional 20-25 minutes, until the crust is golden brown.
Remove the bread from the oven and let it cool completely on a wire rack before slicing and serving.
