Mix starter with water, then add the flours.
Mix then switch to wet hands to keep mixing.
Rest 30mins covered with a wet tea towel.
Mix in the salt and the tsp of water.
Squish all together then pinch in the sides to make a ball.
Leave covered again (Sumer = 6-8hrs, Winter = 8-10hrs)
Tip out onto floured surface + pull the edges in again. Dust dough and banneton with flour then place seam side up in the banneton.
Either: put in fridge and bake the next day, OR leave out for 2hrs at room temperature.
Preheat cast iron pot @ 230°C for 45 mins.
Tip out dough onto baking paper, score it, lower into pot, spray with some water.
Oven covered @ 220°C for 35 mins.
Remove the lid and oven for another 15 mins or until golden brown.