In a mixing bowl, combine 500 g of all-purpose flour and 10 g of salt. Mix well to ensure the salt is evenly distributed.
In a separate bowl, mix 350 g of water with 100 g of your active sourdough starter until fully combined.
Gradually add the wet mixture to the dry ingredients, using a dough scraper or wooden spoon to combine until no dry flour remains. You should have a shaggy dough at this point.
Cover the bowl with plastic wrap or a kitchen towel and let it rest (autolyse) for 30 minutes.
After resting, perform a series of stretches and folds in the bowl every 30 minutes for the next 3 hours.
Once the stretching and folding is complete, let the dough rise at room temperature until it has doubled in size; this could take 4 to 6 hours.
Carefully transfer the dough to a lightly floured surface and shape it into a round loaf.
Place the shaped dough into a well-floured banneton, seam side up. Cover it with a towel and allow it to proof for about 1-2 hours.
Preheat your oven to 450°F (232°C) with a Dutch oven inside for at least 30 minutes.
When ready to bake, carefully invert the dough onto a piece of parchment paper. Score the top with a sharp knife or blade.
Use the parchment to lift the dough into the hot Dutch oven. Cover it with the lid and bake for 30 minutes.
Remove the lid and bake for another 10 minutes or until the bread is golden brown and has a crusty finish.
Remove the bread from the oven and let it cool on a wire rack for at least 1 hour before slicing.