100g starter
200g water
300g bread flour
7g sea salt
Mix flour and water and autolyse for 1hr. Add starter and salt and mix. Do 3 sets of strech and folds every 30min. Cover and leave until doubled in size and wobbly in the bowl.
Pre shape, leave for 20min. Shape into a round ball and put in proofing basket. Place in a fridge for a minimum of 3hrs. Place in a lined duch oven/caserole dish, cover and bake for 30min at 250C. Uncover and bake another 15min at 230C. Take it out and place on a cooling rack for at least 1hr before slicing.