In a medium sized mixing bowl sift flour, crumble the yeast and rub it into the flour using your palms.
Add water and extra virgin olive oil and knead for about 5 minutes.
Sprinkle salt over the dough and knead until soft, smooth and a non sticky dough is obtained.
Form a dough ball, transfer to the lightly floured mixing bowl, cover with plastic wrap and leave at 20°C (68°F) overnight, or for about 8 hours.
Day 2 – Dough
Deflate the dough, knead briefly for 1-2 minutes. Form the dough ball, return it to the lightly floured mixing bowl, cover with plastic wrap and leave at 20°C (68°F) for 1 hour.
Oil lightly 30cmx 40cm (12″x16″) baking pan.
Transfer the dough to the pan and using your fingers gently press and spread/ flatten the dough in the pan. Don’t try to force it by pulling and stretching the dough!
Cover the baking pan with plastic wrap and keep at room temperature for another 2 hours. During this time make a topping sauce.
Topping Sauce
In fresh water rinse anchovies and salted capers.
Peel and finely slice onions. Add olive oil and braise in a shallow skillet over medium heat (5 out of 10) for about 10 minutes.
Stir in tomato passata, reduce heat to low (2 out of 10) and cook until the sauce thickens (liquid reduces for about 1/3). Stir frequently to prevent burning. Taste the sauce and season to taste.
Set aside and let cool completely.
Assembly/Baking
Preheat the oven to 200°C (392°F), rack at the bottom.
Using your hands gently spread the topping on top of the dough.
Spread evenly capers, anchovies, olives and garlic.
Sprinkle with dry oregano and drizzle with olive oil.
Bake for 25 minutes or until golden brown. Properly cooked Sardenaira must have a lightly colored dough that is soft but with a crunchy bottom.