This classic sauce takes its spiciness from black pepper and dried chiles and its depth of flavor from guanciale, Italian salt-cured pork jowl. If you can't find it, use pancetta, which is available at better supermarkets.
Carrabba s Cavatappi Amatriciana (Side Dish Pasta) from Food.com: This is an approximate verision of Carrabba's. This is served in the restaurant as a side dish but would be just fine as a main dish when pancetta is added in. Cavatappi pasta is a short tubed corkscrew or S-shaped pasta. It can be hard to find but I was able to find it called "Twists" by the pasta brand DaVinci (blue bag).