In a large mixing bowl, whisk together the sourdough starter, water and extra virgin olive oil. With a large spoon, stir in the fine sea salt (don’t whisk…once you add salt, the mixture tends to stick to the whisk).

Using the same spoon, mix in the flour until everything is evenly combined and no dry flour patches remain. Scrape down bowl with dough scraper to keep everything tidy.

Cover bowl with tea towel, bowl cover, shower cap or plastic wrap and let sit for 30 minutes at room temperature.

After the dough has rested for 30 minutes, wet your hand to prevent the dough from sticking and perform your first stretch and fold. Your aim is to perform three sets of stretch of & folds within the first 2 hours of the dough proofing, spaced roughly 30 minutes apart from one another.

After you’ve performed your third stretch and fold, cover the bowl and let the dough sit undisturbed, at room temperature, for around 3.5-4 hours. Basically, we are looking for the dough to have grown in size and look puffy, jiggly and full of air.

Cover the bowl with plastic wrap, a reusable plastic shower cap and place into the fridge overnight. It will continue to grow a bit in the bowl overnight, so just make sure there is room for the dough to expand.

Prepare your 9” x 13” (23cm x 33cm) baking tray (also called a quarter sheet pan). Put a tiny bit of oil on the tray, rub it all around and then place a sheet of parchment paper on top and press down.

Using a curved dough scraper or oiled hands, gently release the dough from the sides of the bowl and tip the dough into your oiled and lined tray. Now, you are going to oil your hands and fold one side of dough towards the middle of the blob of dough. Repeat with the other side.

Cover the tray by placing an inverted tray of the same size or bigger on top of it. You just want to ensure the dough isn't being exposed to air because it may dry out while proofing.

Let proof in tray for about 2 - 3 hours. The dough will have spread a lot in the tray over this period of time.

Once you think the dough is ready (it will be floofy and jiggly when you shake the tray), it’s time to preheat your oven to 220C/430F.

Drizzle the top of the dough with a little more extra virgin olive oil and then rub a bit of the oil onto your hands. Using both hands, press your fingers into the dough, gently touching the bottom of the tray.

Top with a sprinkle of flaky sea salt. Add anything you’d like to the top by gently pressing toppings into the little dimples.

Bake your focaccia for about 22-25 minutes in a 220C/430F oven. Check the focaccia after 22 minutes and remove from oven when it’s reached a deep golden brown colour.

I let it cool for a couple of minutes in the pan and then I transfer it to a cooling rack so the bottom doesn’t steam while sitting in the tray.

Let cool for at least 15-20 minutes before cutting in with a sharp bread knife!