The Rome IndexCacio e pepe — the guide
Rome's most famous pasta: three ingredients, endless ways to get it wrong.
What it is
Three ingredients: tonnarelli or spaghetti pasta, Pecorino Romano cheese, and black pepper. The technique is the whole dish — the cheese must emulsify into a smooth sauce with pasta water rather than clumping into a stringy mess, which takes practice and the right ratio of starch to fat.
How to spot a good one
A correct cacio e pepe is glossy, cohesive and clings to the pasta. A bad one is either dry and powdery or has visible clumps of unmelted cheese. The pepper should be coarsely cracked and toasted, not fine ground — you should be able to smell it hitting the hot pan.
Where to eat it in Rome
Testaccio and Monti both have trattorias where it's made properly. Avoid anywhere listing it at under €10 in the tourist center — the ingredients alone make that implausible unless something's been compromised.