Combine dry ingredients - Add the flour, salt, sugar and yeast to a large mixing bowl and whisk to combine.
Mix dough - Add the water to the dry ingredients and a tablespoon to mix until a very wet and sticky dough forms. Make sure any ingredients at the bottom of the bowl have been mixed in properly.
Rise 1 - Cover the dough with 2 tbsp olive oil. Cover with plastic wrap and let it rise for one hour in a warm spot until it’s doubled in sized.
Lift and fold - Picture the dough as having four corners. Use wet hands to stretch the dough up and then over itself. Do this on each 4 sides. This will help develop gluten strands to make the dough even chewier!
Rise 2 - Transfer the dough to the fridge and let it slow rise for 8-72 hours. The longer you leave it, the deeper the flavors it develops.
Thaw the dough - Take the dough out of the fridge and let it thaw for 30 minutes.
Form dough in tin - Grease a 9x13-inch baking tin with 2 tbsp of olive oil. Pour the room temperature dough on top of your baking dish and use your hands to spread or stretch out as much as you can. If it’s not perfectly at each corner, it’s ok!
Rise 3 - Cover with plastic wrap and let it rest between 1-2 hours in a warm spot. It will puff up, rise and bubble. Once risen, drizzle with 2 tbsp of olive oil and sprinkle with rosemary. Use your fingers to indent the dough. Bubbles will appear. You can pop those or leave them. Add garlic into some of the indents.
Preheat oven - 20 minutes before the bread is ready to be baked, preheat your oven to 220C / 430F (fan on), 200C / 400F (fan off). I prefer baking with the fan on for this recipe.
Bake - Bake for 40 minutes or until golden and crispy. Sprinkle with sea salt flakes and serve warm or cold.