Finely cube the guanciale.
In a saucepan large enough to hold the pasta, cook the guanciale over a very low flame until crisp and crunchy.
Whisk the eggs, cheese and black pepper together with a fork until it's creamy.
Cook the pasta in boiling, salted water according to package instructions, until al dente.
Drain the pasta, but reserve a cup of the cooking water.
Reheat the guanciale, and quickly toss in the pasta until fully coated.
Mix in in the egg mixture until creamy.
If the pasta is too dry add some pasta cooking water, by the tablespoonful.
Sprinkle lightly with more grated cheese.
Place in a serving dish and serve.