Cook the spaghetti in a large pot of boiling salted water until al dente.
Meanwhile, cut the guanciale into small pieces and fry in a hot pan until crispy.
In a separate bowl, beat the eggs and mix with the cheese and a generous amount of black pepper.
Drain the pasta, reserving some of the pasta water.
Immediately toss the hot pasta with the cooked guanciale, then add the egg mixture and mix quickly. The heat of the pasta will cook the egg slightly and form a creamy sauce. If needed, add a bit of the reserved pasta water.
Serve with extra cheese on top and enjoy :)
Notes
Have all your ingredients prepped and ready before you start cooking. Timing is critical in this dish.
Use a big enough pot to boil your pasta. It needs plenty of space to cook evenly.
Keep some of the pasta water. The starchy water helps to thicken and bind the sauce.
Be careful not to scramble the eggs. To avoid this, make sure your pasta is hot but not too hot when adding the egg mixture.
Use freshly ground black pepper and freshly grated cheese for best flavor.