Begin by dicing the guanciale or pancetta into small cubes. Heat a large skillet over medium heat and add the diced pork, cooking for about 8-12 minutes until golden brown and crispy. Reserve the rendered fat and remove the crispy meat.

In a large pot, bring salted water to a rolling boil. Add the spaghetti and cook until al dente, around 8-10 minutes. Reserve about 1 cup of starchy pasta water before draining.

In a mixing bowl, whisk the eggs and combine with grated Pecorino Romano and Parmesan cheeses. Gradually add a small portion of hot pasta water while whisking to temper the eggs into a creamy sauce.

Return the drained spaghetti to the skillet off the heat, pour in the egg and cheese mixture, and rapidly toss to combine. Add reserved pasta water as needed to reach desired consistency.

Plate your Italian Spaghetti Carbonara, garnishing with additional grated cheese and freshly ground black pepper. Serve warm and enjoy.