There are options for the mix of flours and also for the addition of other ingredients like olives. Timings are given but these can be shifted backwards or forwards to suit.
The timings here assume starting at 8am but can be shifted backwards or forwards or adjusted without any trouble.

First of all make the sponge (8am)

Ingredients

350g Water

200g Strong White Flour

50g Strong Wholemeal Flour

100g active sourdough starter

Note: The recipe here assumes 80% white and 20% wholemeal. However I have used 80% white and 20% spelt with great results and assume that other flour combinations will also be worth exploring.

Mix ingredients together in a bowl and stir until you have a smooth sponge. Cover with cling film or a tea towel.

8 hours later (4pm)

Add the following ingredients to the sponge and combine:

250g Strong White Flour

50g Strong Wholemeal Flour

10-12g Salt

Note: At this point I have also sometimes added other ingredients. Green olives and roughly chopped pieces of lemon from a jar of sliced lemons in lemon juice is a favourite combination. Just be a bit careful if the added ingredients are increasing the water content (as with the lemons) and reduce the initial water a little to compensate. The addition of a seed mix is another favourite although in that case the seeds absorb some of the water so require a bit more water to be added (maybe 25-50g)

Knead in the bowl for about 5 to 10 minutes

Cover again with the cling film or tea towel allow to prove for 3-4 hours.

After the 3-4 hours (at 7-8pm) tip the dough out onto a floured board or counter and knead for 5 to 10 minutes until smooth and springy. Shape into a round or oval ball to suit your proving basket or banneton.

Flour the proving basket and place the dough ball upside down in the basket. Flour the top and place in a plastic bag. The dough can now be put in the fridge or somewhere cold to prove overnight. The fridge works fine although it is probably a bit colder than ideal. In the winter I usually leave it to prove in the garage or an unheated room where it will be cold enough but not quite as cold as the fridge.

In the morning at about 7am to 8am pre-heat the oven to 230C with the dutch oven inside.

Upturn the dough ball onto a sheet of baking paper and score the surface to allow for the bread to expand in a managed way.

Remove dutch oven from oven, take off the lid, and carefully lower the dough on the baking paper into the dutch oven.

Replace the lid and put the dutch oven back into the oven.

Bake for 25 to 30 minutes with the lid on.

After the 25 to 30 minutes remove the lid and turn the heat down to 205C. Bake for a further 25 to 30 minutes.

I set the timer on the oven to cook for 55 minutes in total with roughly half with the lid on and half after taking the lid off.

When finished turn the loaf out onto a wire rack and allow to cool before slicing. We generally use half the loaf on the day and put the other half in the freezer.