Cut the guanciale into small pieces.
Place it in a cold skillet and cook over medium-low heat until the fat renders and the meat becomes crisp.
Whisk the egg yolks, whole egg, Pecorino Romano, and black pepper in a bowl.
Cook spaghetti in salted boiling water until al dente.
Reserve at least 1 cup of pasta water before draining.
Toss the hot spaghetti with the rendered guanciale fat.
Remove the pan from direct heat and add the egg-and-cheese mixture.
Toss continuously while adding pasta water gradually until the sauce becomes glossy and creamy.
Add the crispy guanciale and toss again.
Serve immediately with extra Pecorino Romano and freshly cracked black pepper.
