In a glass bowl, add water and yeast. Mix the yeast into the water and let it sit for a couple minutes.
Add in the rest of the ingredients for the starter. Mix well until everything is fully incorporated.
Wrap the bowl with clear wrap, making sure not to tightly seal the bowl. Let the starter breathe a little and keep it in a dark place at room temperature. Stir every 12 hours until making the dough. The starter will rise and shrink each day and you should see bubbles, letting you know that the yeast is being activated!
On day 5, combine all ingredients into a bowl, and knead for 10 minutes on low if using a machine; if kneading by hand, knead for 20 minutes until dough is stretchy yet doesn’t stick to your hands.
While the dough is kneading, store your starter for future use. Your starter will last forever as long as you maintain and care for it. It can stay in the fridge and be fed once a week with a teaspoon of sugar. To replenish your starter, simply add 1 cup of flour (125g) and ½ cup of water (120ml), mix, and place it back in the fridge. Leave it out overnight to get to room temperature before preparing the dough.
Place kneaded dough into a large floured bowl with a towel over the top, then sprinkle flour and let it rise for 12 hours.
Place risen dough onto a floured board and knead for a few minutes. Place it into a floured proofing basket or a medium bowl, sprinkle flour and let it rise for another 4 hours.
Preheat oven to 480°F (250°C).
Flip the dough onto a parchment paper, and transfer the dough and paper into a large cast-iron dutch oven.
Score the top of the bread.
Place the lid on top and bake for 30 minutes.
Take the lid off and bake for another 15 minutes or until the crust is golden brown.
Transfer onto a cooling rack and let it rest for an hour. Knock the bottom of the bread to listen for a hollow knock.