Steps

Bring a pot of salted water a boil and cook the rigatoni till al dente. We don't want to use too much water because we want starchy pasta water for your sauce. Lightly salt the water to avoid making the sauce too salty since pecorino is already salty

While the pasta is cooking, add guanciale in a cold pan on medium heat to allow the fat to render and cook until golden brown. The fat from the guanciale will render out and create a flavorful base for the sauce.

Add the cooked pasta to the skillet with the guanciale. Toss well to coat the pasta with the rendered fat. Add a bit of the reserved pasta water to help emulsify the sauce and coat the pasta evenly.

Remove the skillet from the heat and quickly add the grated Pecorino Romano cheese. Seaso with freshly ground black pepper and toss again.

Serve the pasta hot, with an extra sprinkle of Pecorino Romano and black pepper on top if desired.