It is a large (a round measuring about half a meter across), very thin, crispy flatbread made from durum wheat, salt, yeast and water which has been baked in an extremely hot, wood fired bread (pizza) oven. It is cooked for a few minutes in the front of the oven until it puffs up, it is then split into two and each piece is re-baked.
The bread was originally baked for shepherds who were away from home for many months with their flocks. Pane Carasau will last up to a year so was an invaluable source of food for them to take with them. It can be eaten just as it is, warmed with oil or soaked in water to soften and expand it.
It is generally referred to as 'carta di musica' which means music paper, due to its extra thin, almost parchment like quality.