Making a starter is not absolutely necessary but it will provide a more complex flavor for the dough. Combine flour, water and the yeast in an airtight container and put it into the fridge for 4 – 6 hours. It will double in size so choose a big enough box.
Dough
Measure flour, water, extra virgin olive oil, salt and fresh yeast into a kneading bowl. Add the starter in too. It tends to stick to the box but mixing it with some flour from the bowl will help salvage every bit without much effort. If starter is not used, add the equivalent amount of flour and water to the bowl.
Knead until a uniform texture forms.
Stretch the dough into a baking sheet. Rub it with a thin layer of extra virgin olive oil so it won't dry out.
Cover the dough then let it rise at a 68°F – 81°F /20°C – 27°C temperature place until doubles, about 45 - 90 minutes. Sprinkle rosemary leaves on top of the risen dough. Poke holes through the dough until our fingers touch the bottom of the baking sheet.
Place the dough into a preheated 360°F / 180°C oven until golden brown spots start to appear on top, for about 30 - 40 minutes. For a more crispy crust, place the dough onto the bottom shelf of the oven or keep it in the middle for a softer touch.
Brush some extra virgin olive oil on top for extra softness and flavor. Slice and serve!