Your starter should be active and vigorous. Feed it again last thing in the evening of the day before you want to bake and leave in a warm place overnight. It should double in size by the time you mix it into the dough the following morning
Early morning (6-8 hours after feeding starter) mix together all ingredients. Mix well by hand or use a stand mixer for 5-10 minutes for better results
Mix well, scrape down bowl and rest for 30 minutes.
Stretch and Fold the dough, then rest for 30-40min. I do a coil fold at each stretch.
Stretch and fold 3 more times. Followed by a final 30 minute rest.
Preshape the dough with a coil fold then rest uncovered another 15 minutes.
Do a final coil fold trying to avoid degassing the dough then load into floured bannetons (I use rice flour to prevent sticking), with the seam side up (ie the top of your loaf is at the bottom of the banneton to pick up that nice rattan shape). At this point you can roll in seeds such as sesame poppy etc.
Allow to proof another 3-4 hours until almost doubled in size then refrigerate overnight.
1 hour before baking get your oven preheating to 250c. It needs a full hour to heat the baking stones and dutch oven properly.
Bake time, transfer out dough to parchment paper. Score with a bakers lahm, then load via some parchment paper into the screaming hot preheated dutch oven. Spritz well with water then quickly cover to trap the steam and return to oven.
Bake for 20 minutes with lid on. Remove lid and bake another 15-20 minutes until desired level of scorch is reached.
Remove from oven and allow to cool FULLY on a wire rack. Don't be tempted to slice into your newly baked loaf of bread till it's cool. It's still cooking while it's cooling down and your patience will be rewarded if you wait.