What you need:
Ingredients 
800g of Odlums Strong Flour
10g of salt
460ml of water
320g of sourdough starter (see recipe below)
 
Sourdough Starter Recipe 
How to:
You can make this two ways, by hand or in your stand mixer. Both work out the same. 
Start by adding all the ingredients to a bowl. If doing this by hand, mix with a fork to combine, on the machine turn it onto a medium speed and mix with a dough hook for 5-8mins. 
By hand tip the dough out onto the surface and knead really well for a good 10 minutes. 
Once kneaded place the dough into a bowl and leave to prove for 4 hours. 
4 hours later knock back the dough by punching all the air out and shape with your hands into a nice round ball. 
Flour your proving basket and tip the dough with the flat side into the basket. Cover with a damp tea towel and leave to prove for a further 3 hours. 
Preheat the oven to 230oC. Place a tray of boiling water into the bottom of your oven to create some steam. Tip the dough out from the proving basket onto a floured tray. Bake for 30-35mins and enjoy the most delicious bread ever.