Make a well in the flour, and dissolve yeast in warm water with a pinch of salt. Mix to make a firm smooth dough, then cover and allow to rise for a couple of hours.

Tradition has it that by pounding on the dough in the right way, it makes a particular hollow sound, similar to that of a muted drum.

Make the "conza" (the dressing) as follows.

Slice a large quantity of onion, braise in extra-virgin olive oil (preferably from Sicily), covered so that steam is formed and the onion does not brown.

Add peeled tomatoes, previously flavored with a few garlic cloves, which will be removed. Finish cooking and make a thick aromatic sauce.
Pout the dough into a buttered rectangular tin by hand to make a sheet about 0.8 inch thick.

Press anchovies de-boned and cut into pieces into the dough, in desired amount. Place thin slices of cheese onto the dough.

Top with a generous layer of sauce and sprinkle with grated cheese and fresh oregano. Dress with olive oil and put into a very hot oven (425°F).

If the sauce is not reduced enough, mix some breadcrumbs previously toasted in a lightly-greased pan with the grated cheese.

Other suggested recipes 

• Sicilian Pizza
• Seafood Rice Croquettes
• Calzone