Take 200g of your starter and mix with 700g of water in a large bowl. Mix well until the two combines into a milky colored liquid.

Measure out 900g of AP flour and 100g of whole wheat flour (making it a total of 1kg)

Add flour to the bowl and use hands to incorporate with the water (Jon suggests using hands, but I prefer using a spatula. Keeps the hand clean!) Once it's well mixed, leave it covered for 30 minutes (I have taken to leaving it for a good 1 hour).

After the half/one hour rest, add 20g of salt into the mixture, and use hands (this is when I do actually use my hands) to mix it in. Once well mixed, cover and leave it for 30 minutes.

After 30 minutes, stretch and fold - Round 1 - leave covered

After 30 minutes, stretch and fold - Round 2 - leave covered

After 30 minutes, stretch and fold - Round 3 - leave covered

After 30 minutes, stretch and fold - Round 4 - leave covered

Leave in the bowl for 4 - 5 hours (depending on how warm your part of the world is)

After the wait, pour the dough out onto your work surface, do a stretch and fold once and let it rest for 30 or so minutes. In the meantime prepare your proofing basket.

Do another round of stretch and fold, and then place dough in the proofing basket and then wait for 30 or so minutes.

Transfer dough to a Dutch Oven, score and bake covered for 20 - 25 minutes. At 500F

Remove the cover and bake for another 20 - 25 minutes or until it reaches the level of browning you are satisfied with at 450F

That's it - it works for me so I hope it does for you too! I got one at stage no. 9 now on my kitchen counter :) Good luck!