Cacio e Pepe – literally cheese and pepper – is a pasta dish from the Lazio region of central Italy that consists of just Pecorino Romano cheese, black pepper, tonnarelli pasta and water. And it is a fabulously smooth, creamy dish.
Yet every Italian chef knows this simplicity is deceptive. Get the proportions of ingredients wrong and Cacio e Pepe quickly becomes a soggy, lumpy mess. Perfecting the dish is surprisingly tricky, but how come?
Now we get an answer thanks to the work of Giacomo Bartolucci at the University of Barcelona and colleagues who have explored the complex behavior of the emulsion that forms when pecorino cheese is added to water used to cook pasta, which is filled with starch. It turns out that the proportion of cheese, the amount of starch in the water and the temperature must all be carefully controlled to achieve the perfect result.
