Step 1

Bring a large pot of lightly salted water to a rolling boil for the pasta. In a large frying pan, heat the oil until lightly smoking over medium heat, then cook the guanciale or pancetta until crispy, about 6 minutes. Keep warm.

Step 2

Drop the pasta into the water and cook until "al dente" according to the package instructions. As the pasta is cooking, warm a large serving bowl. Place the egg yolks in the bowl along with three quarters of the cheese mixture along with the ground pepper. Use a whisk and blend until well mixed.

Step 3

Drain the pasta, reserving a small cup of the pasta water. Add the drained, steaming hot pasta into the bowl with the eggs, along with a little of the pasta water, toss well to lightly cook the eggs and coat the pasta with the egg mixture. Add the warm guanciale or pancetta, and toss again to mix well. Serve the pasta in individual bowls with a sprinkling of the parsley and the remainder of the cheese.