Step 1: Cook the Guanciale and Nduja

• Heat the olive oil in a large frying pan over medium heat.
• Add the guanciale or pancetta and cook until crispy, about 6 minutes.
• Stir in the nduja and mix well until melted and incorporated. Keep warm.

Step 2: Cook the Pasta

• Bring a large pot of lightly salted water to a rolling boil.
• Add the spaghetti or bucatini and cook until al dente, according to the package instructions.

Step 3: Prepare the Egg Mixture

• While the pasta is cooking, warm a large serving bowl.
• In the bowl, whisk together the egg yolks, grated Pecorino Romano, and cracked black pepper until well combined.

Step 4: Assemble the Carbonara

• Drain the pasta, reserving about 1/2 cup of the pasta water.
• Return the pasta to the pot and toss it with the warm guanciale and nduja mixture.
• Quickly transfer the pasta to the bowl with the egg mixture, tossing vigorously to coat the noodles while slowly adding a little pasta water to help emulsify the sauce.
• Continue tossing until the eggs thicken into a creamy sauce without scrambling.

Step 5: Serve

• Divide the pasta among serving bowls.
• Sprinkle with fresh parsley and additional grated Pecorino Romano cheese. Serve immediately.