Before you want to start, make sure your starter is active. To check, drop a small teaspoon of the starter in a cup of water and if it floats, it's ready to go. Make sure all your ingredients are at room temperature. If the starter was in the fridge, you may want to take it out well in advance.
To make the sourdough, add the water, starter, and the olive oil in a large mixing bowl and whisk lightly. Add the flour and salt to this wet mix and bring everything together with a spatula. You will get a shaggy dough.
Cover the bowl with a kitchen towel or a plastic wrap and let your dough rest for at least 30 minutes. This is known as the autolyze stage when the dough absorbs the water absorbs water. The proteins and starches in the flour start to break down.
Now comes the folding stage. This is when you work the dough at regular intervals. It can also be seen as the bulk fermentation stage. To start, remove the wrap and start 'stretching and folding' the dough.
To fold the dough, grab it on one side, stretch it upwards and fold over the top. Rotate the bowl by about a quarter of a circle and repeat the action. Keep doing this till you come a full circle. Try and space out each fold about 30 minutes apart, letting the dough rest covered with a kitchen towel in between. The shaggy and wet dough will become smooth and tighten up.
After folding, let the dough rest in a warm and dry place. This will take anywhere from 3 to 12 hours. We recommend letting it rest overnight so that you have the dough ready to work in the morning. It will increase in volume by almost double or slightly less than that.
At the end of this period, prepare your workspace by lightly dusting it with flour. Take out the flour from the bowl on to your counter. Use a bench scraper to cut the dough in two or more parts, depending on how big you want your loaves.
Now start shaping each portion. Work on a non-floured surface. Take one side and fold the top towards the center. Give it a slight turn and fold another section. Keep going till you reach a full circle. Flip the dough so that the seams are now at the bottom. Using your hand, gently rotate the dough with a slight cupping action at the bottom so that you have a round-shaped loaf that has a smooth surface.
Prepare your loaf tin or dutch oven by covering the bottom with flour. Alternatively, use a parchment paper. Place the prepared dough in the bowl. Let it rest for at least an hour. You can also use a proofing basket for this step. In that case, liberally flour the basket and transfer the dough to the dutch oven/loaf tin before baking.
Before putting it in for baking, preheat the oven to 450 degrees F. Before putting the bread in for baking, make sharp slashes on its surface. You can use a sharp knife or a bread lame. I've even known a chef to use a special razor he keeps for just this purpose!
Cover the baking dish, reduce the temperature to 400 degrees, and put the bread in for baking. After 20 minutes, remove the lid and bake the bread for an additional 40-50 minutes or till it has the trademark brown crust.
Open the oven door slightly in the last 10 minutes of baking. When the bread is done, take it out of the pot using spatulas and let them cool completely. It is important that you let this cool for at least an hour.
Your lovely delicious sourdough bread is ready. Enjoy a sliced toast with butter and tea!