Combine the flour, yeast, salt, and sugar in a large bowl.

Pour over the lukewarm water. Mix well with a spatula until a sticky dough is formed.

Pour a teaspoon or two of olive oil on the surface of the dough and rub it all over.

Cover with plastic wrap and refrigerate for 18–24 hours. I kept it for 24 hours.

When you’re ready to bake, grease a 9″x13″ or 10″x12″ pan. Line the bottom with parchment paper. You may not need to do that if your pan is non-stick.

I used a 10″x12″ pan and lined it too.

Take out the refrigerated dough. Oil your hands and gently bring the proofed dough in from the sides of the bowl.

Fold the dough over itself. Turn the bowl a quarter of the way and fold the dough over itself again. Do 3 more quarter turns of the bowl with folding over the dough each time.

Repeat this step once more.

Pour 2 tablespoons of olive oil in the center of the prepared pan.

Gently place the deflated dough on the olive oil. Roll it a couple of times to coat it well with oil.

Cover this with plastic wrap or a kitchen towel and keep in a draft-free place for 2–4 hours or until the dough doubles and covers the pan.

Mine doubled in 1.5 hours.

Preheat the oven to 220 C.

Sprinkle rosemary (if using) all over the surface of the dough.

Pour over the remaining 2 tablespoons of olive oil on the dough and spread it all over. Dimple the dough using your fingers. Sprinkle the sea salt.

Bake the bread at 220 C for 25–30 minutes, until the top is golden brown. The bottom of the bread should be crispy.

Let the bread rest in the pan for 5 minutes before turning it out on a cooling rack. Slice warm or let it cool completely. Enjoy!