Cacio e Pepe
Cacio e pepe is three ingredients (Pecorino Romano, black pepper and pasta water) and no butter, cream or oil. It fails for one reason only: heat, because Pecorino splits above roughly 65 °C (150 °F).
Cacio e pepe is shepherds' food. Pecorino keeps, pepper keeps, dried pasta keeps, and the transhumance routes that ran from the Roman countryside down into Puglia meant men carried exactly those three things in their saddlebags. In Rome the dish became a fixture of the trattorie of Testaccio and Trastevere, where it is traditionally made with tonnarelli, the square-cut fresh egg pasta the city calls its own. Everything about it is subtraction: no garlic, no oil, no butter, no herbs, and certainly no cream.
What makes it work is physics rather than cooking. Pecorino Romano is a hard, salty sheep's cheese with very little moisture; when it hits a hot pan the casein proteins tighten and squeeze the fat out, and you get a stringy lump in a puddle of grease. Keep the temperature below about 65 °C (150 °F) and add starch from the pasta water, and the same cheese emulsifies into a glossy sauce. So you deliberately cook the pasta in very little water to concentrate the starch, you grate the cheese as finely as you can, and you build the sauce off the heat. The pepper is not a garnish: cracked coarse and toasted in a dry pan, it supplies the aromatic backbone that keeps the dish from being simply salty.
Ingredients
- Tonnarelli, spaghetti or spaghettoni360 g (12.7 oz)
- Pecorino Romano DOP, grated as finely as possible200 g (7 oz)
- Black peppercorns2 tsp (about 6 g)
- Water for the pasta2.5 litres (2.6 qt) only
- Coarse salt4 g per litre, half what you normally use
Method
- 01Bring 2.5 litres of water to the boil with 10 g of salt in total. Using less water than usual is deliberate: it leaves the cooking water thick with starch, which is what will hold the sauce together.
- 02Crush the peppercorns coarsely in a mortar, or under the base of a pan. Toast them in a dry frying pan over medium heat for 30-40 seconds, until they smell fragrant, then set the pan aside off the heat.
- 03Grate the Pecorino on the finest side of the grater, or in a food processor, and leave it at room temperature. Cold, coarsely grated cheese is the single most common cause of a clumped sauce.
- 04Cook the pasta, stirring often to keep the starch moving, and drain it two minutes before the time on the packet. Reserve at least three ladles of the cooking water.
- 05Put 150 g of the Pecorino in a bowl with about half the pepper. Add four tablespoons of the cooking water, cooled for a minute so it is warm rather than boiling, and work it with a whisk into a smooth, thick paste the texture of double cream. Add water a spoon at a time if it resists.
- 06Tip the drained pasta into the pepper pan with a ladle of cooking water and toss over low heat for 30 seconds, so the pasta finishes cooking and the water thickens slightly.
- 07Take the pan off the heat and wait a full minute. You should be able to hold the back of your hand against the base of the pan; that is roughly 65 °C, the point below which the cheese will emulsify instead of splitting.
- 08Add the Pecorino paste and toss hard for 30-40 seconds, loosening with cooking water a spoonful at a time until the sauce coats every strand and slides slowly off the tongs.
- 09Serve at once in warmed bowls, finished with the remaining cheese and pepper. Cacio e pepe sets as it cools and does not wait.
What ruins it
Every failure comes from heat or from the cheese. Never add Pecorino to a pan that is still on the flame: the proteins seize and the fat separates, and once split it cannot be brought back. If you are unsure, build the sauce in a metal bowl set over the pasta pot with the heat switched off, which caps the temperature naturally.
Do not use pre-grated cheese: it is coated with anti-caking starch and cellulose that will make the sauce grainy. Do not substitute Parmigiano Reggiano, which is a cow's-milk cheese with a different fat and salt profile and gives a flatter, sweeter result. A mix of three parts Pecorino to one part Parmigiano is a legitimate softening, but it is no longer the Roman dish. Do not salt the water normally, because Pecorino Romano is one of the saltiest cheeses made. Do not add butter, oil or cream to force creaminess: you are covering up a technique problem rather than solving it. And use ground pepper only as a last resort: pre-ground pepper has lost its volatile aromatics and just tastes hot.
About the ingredient: Pecorino Romano →
Frequently asked questions
Why does my cacio e pepe turn into clumps?
The cheese hit something too hot. Above about 65 °C (150 °F) the casein in Pecorino tightens and expels its fat, producing strings in a greasy pool. Make a paste with warm pasta water first, then emulsify it in a pan that has been off the heat for a minute.
Can I use Parmesan instead of Pecorino Romano?
It will taste good but it will not be cacio e pepe: cacio is the Roman word for the sheep's cheese itself. Pecorino Romano is saltier, sharper and made from sheep's milk. If it is too aggressive for you, replace a quarter of it with Parmigiano Reggiano.
What pasta should I use?
Tonnarelli, the square-section fresh egg pasta, is the Roman choice, and its rough surface holds the sauce. Dried spaghetti or the thicker spaghettoni work well; bronze-die pasta is worth the small extra cost because the rough surface releases more starch.
Is there butter or cream in cacio e pepe?
No. The authentic dish is Pecorino Romano, black pepper and starchy pasta water. Butter appears in some restaurant versions as insurance against splitting, and cream never belongs in it at all.