In a large pot, bring salted water to boil (about 8 cups of water should suffice).
Meanwhile, prepare your ingredients: slice the guanciale (or pancetta) into thin slices, separate the yolks from the whites (we don’t need the whites, so set them aside), grate your cheese.
When the water begins to bubble, toss in your spaghetti.
Meanwhile, in a large skillet or wok, fry the guanciale for a few minutes.
After few minutes, your spaghetti should be “al dente” (that means almost ready), so you can go ahead and toss them into the wok, over the meat.
Let the cook for a couple of minutes, while you mix the egg yolks with the grated cheese. Add 2-3 tablespoons of cooking water (from your spaghetti water) in order to make them more creamy.
Leave some cheese aside, for serving.
After a couple minutes, take the spaghetti off the stove and add the egg mixture on top.
Mix everything carefully.
Serve with grated cheese on top and a pinch of pepper.