Cooking instructions: Cut the guanciale into layers. Combine the egg yolks with the grated cheese and a pinch of black pepper. Brown the strips of guanciale for 2 minutes in a pan, until crisp, then turn off the heat and leave to cool. Bring a large pot of water to a boil. Add salt. Cook the pasta, setting aside a ladleful of the pasta cooking water, until al dente. Drain. Pour the reserved hot water into the frying pan with the cooled guanciale, then transfer the pasta to the same pan and mix together. Add the yolk and cheese mixture, stirring rapidly. In the warm pan with the hot pasta, the eggs will cook gently and become creamy – don't stir over heat otherwise the carbonara will become lumpy. It's important to stir quickly to prevent the yolks from congealing and taking on the texture of scrambled eggs. Season with freshly milled black pepper and serve immediately on heated plates.