This sauce is also known as amatriciana. Use pancetta or the traditional choice for this dish, guanciale. The meat gives this simple sauce a rich flavor. If you buy the meat at an Italian market, have the butcher slice it for you, and then cut it into strips when you get home.
SERVING IDEA: Toss with pasta, such as spaghetti, bucatini, cavatelli, macaroni, orecchiette, or penne, and garnish with finely grated Pecorino Romano cheese. MAKE AHEAD: Sauce can be frozen for up to 1 month.