In your stand mixer bowl pour in your sourdough starter, the flour, the salt and if using it, the butter. Slowly pour in your water around the edges of the mixer bowl

Put the dough hook on your stand mixer and let it knead on low to medium speed for about 10-15 minutes. Remove the bowl from the mixer, cover with cling film and let it rest for 1 hour.

Repeat the above – place your bowl back in the mixer and let it knead for another 10-15 minutes. Once done the dough should have formed a nice smooth and a little bit sticky ball. If the dough is too sticky, let it rest for another 10-15 minutes and knead once more.

Cover with cling film and let it rest for 3-4 hours or until it has risen by a quarter (25%) in size.

Line your proofing basket with a terry cloth or kitchen towel and sprinkle generously with flour. Spread the flour on the cloth using your hands.

Tip the dough out from the bowl on a floured work surface. Shape your dough into a taught round ball by pulling one edge at a time and folding toward the center. Flip the dough over and using a dough scraper pull the dough across your work surface to form a round, taught ball.

Cover with cling film and place in the fridge overnight (or longer if you prefer – up to 1 day).

Preheat your oven to 230C/ 450F with your large metal pot (dutch oven) placed inside.

Once pre-heated, remove your dutch oven, take the dough out from the fridge and tip it over in the dutch oven. Score it lengthwise with a sharp razor at a 30 degree angle or cut using scissors.

Cover with the lid and bake for 20 minutes.

Once the 20 minutes are up, remove the lid from your dutch oven and let it bake for a further 15 minutes or until deeply browned

Remove your bread from the oven and place it on an airing rack to cool down.