The dough is made with semolina and water. You can also buy the pasta with porcini mushrooms added to the pasta dough, or with the dough made from spelt flour instead of semolina.
It is usually used with meatless sauces.
Boil for 12 to 15 minutes; stir after first 2 or 3 minutes (but not before.) Use 4 litres (4 US quarts) of salted, boiling water for 1/2 kg (pound) of pasta.
Originally from Umbria, Italy, where reputedly monks were the first to make it.