Cacio e Pepe

Name: Cacio e Pepe
Prep time: 20 min
Total time: 20 min
Cuisine: Italy
Ingredients: 400 g (14 oz) tonnarelli or spaghetti, a thick spaghetti is best; 160 g (5½ oz) Pecorino Romano, very finely grated, at room temperature; or a vegetarian hard cheese (traditional Pecorino uses animal rennet); 2 tsp black peppercorns, plus extra to finish; 20 g (1 tbsp) fine sea salt, for the pasta water

Cheese, pepper, pasta water — and the method that makes them a sauce

Serves: 4
Hands-on: 20 min
Total: 20 min
Level: Some skill

Three ingredients, one technique. The trick is to make the cheese sauce in a bowl with warm, not boiling, pasta water, so the Pecorino melts into a smooth cream instead of seizing into strings.

Ingredients

400 gtonnarelli or spaghetti (14 oz)a thick spaghetti is best
160 gPecorino Romano (5½ oz)very finely grated, at room temperature; or a vegetarian hard cheese (traditional Pecorino uses animal rennet)
2 tspblack peppercornsplus extra to finish
20 gfine sea salt (1 tbsp)for the pasta water

Diet: Vegetarian
Allergens: gluten, milk
Origin: Italy (Rome)

Method

Bring just 2.5 L (2½ qt) water to a boil in a wide pot with 20 g (1 tbsp) salt. Less water means starchier water, which is what holds the sauce together.
Toast the peppercorns in a dry large frying pan over medium heat until fragrant, about 1 minute, then crush them coarsely in a mortar or under a heavy pan. Return half to the frying pan. 1 min
Put the grated Pecorino in a bowl.
Cook the pasta until 2 minutes short of the packet time, stirring often so it does not stick in the small amount of water. 8 min
Ladle 200 ml (¾ cup) pasta water into the frying pan with the pepper and let it bubble for 30 seconds.
Take another 150 ml (⅔ cup) pasta water and let it cool for 1 minute — it should be hot, around 70°C (160°F), not boiling. Pour it gradually onto the cheese while whisking with a fork, until you have a thick, smooth, pourable paste.
Lift the pasta into the frying pan and toss over medium heat for 1–2 minutes until most of the water is absorbed and the pasta is al dente (tender, with a slight bite at the center). 2 min
Take the pan off the heat and wait 30 seconds. Add the cheese cream and toss vigorously, adding more pasta water a spoonful at a time, until the sauce is creamy and clings to every strand.
Serve immediately with the rest of the crushed pepper.

Why it works

Pecorino's proteins tighten and squeeze out their fat when they hit liquid above about 75°C (167°F), which is why cheese dumped into a hot pan turns into clumps. Pre-mixing it with cooler pasta water lets the starch coat the proteins first, forming a stable emulsion before it ever meets the hot pasta. Cooking the pasta in less water concentrates that starch.

Common mistakes

Grating the cheese coarsely: it melts unevenly and clumps. Use the finest holes or a microplane.
Adding the cheese over the heat: always toss off the heat.
Letting the finished dish sit: the sauce tightens within minutes. Have bowls and people ready.