Cooking Pasta

1. Fill a large pot with water, add a generous pinch of salt, and bring to a rolling boil.
2. Add spaghetti and cook until al dente, about 8-9 minutes. Reserve 1 cup of pasta water before draining.

Cooking Pancetta

1. Meanwhile, heat a skillet over medium heat and add diced pancetta or guanciale.
2. Cook until golden and crisp, about 5 minutes. Remove from heat, leaving the rendered fat in the pan.

Making the Sauce

1. In a bowl, whisk together egg yolks and finely grated Pecorino Romano until smooth. Add freshly ground black pepper.
2. Add the drained pasta into the skillet with pancetta fat and toss well to coat.
3. Remove the skillet from heat, slowly pour the egg and cheese mixture over the pasta, tossing quickly.
4. Add reserved pasta water a little at a time to reach a creamy consistency. If curdling occurs, lower the temperature or toss more vigorously.

Serving

1. Taste for seasoning and adjust with additional cheese or black pepper if desired. Serve immediately with extra Pecorino and cracked black pepper.