Boil salted water and cook the spaghetti al dente (usually one minute under the listed cook time)
Cook guanciale (pancetta or bacon work too)
Reserve 2 tbsp of rendered guanciale fat
Whisk eggs, egg yolks, and salt
Reserve 1 cup of starchy pasta water and strain the pasta
Return the pasta to the pot and toss it with the rendered fat
Slowly temper 1/3 of the starchy water into the egg mixture while rapidly whisking it until it comes together as a creamy sauce with a silky texture (add more if needed)
Toss sauce with pasta
Pepper liberally and serve
