Bring a large pot of salted water to boil. Add the pasta and cook until al dente.

In a medium bowl, thoroughly whisk the eggs and yolks. Add the grated parmesan, pecorino, and 1-2 teaspoons of cracked black pepper (adjust according to your preference). Whisk again until well combined.

Chop the guanciale into small bite-sized pieces. Place a large shallow pan over low-medium heat. Add the guanciale and gently heat until the fat becomes transparent and the meat slightly browned; approximately 6-8 minutes. Remove the guanciale from the pan and set aside. 

Once the pasta is cooked until al dente, use tongs to transfer it to the pan with the guanciale fat over low heat, allowing the pasta to continue cooking in the residual fat.

Gradually add approximately ½ to ¾ cup of pasta water to the egg mixture while whisking. This process prevents the egg mixture from scrambling, resulting in a smooth consistency.

Take the pan with the pasta off the heat and add the egg mixture. Stir until it starts to thicken slightly. Then, return to low heat and keep stirring until everything is well combined and creamy.

Return the cooked guanciale to the pan and stir to combine. Serve immediately, garnishing with more black pepper and grated cheese.