Bring a large pot of salted water to a boil and cook spaghetti until al dente according to package instructions.
While pasta cooks, cut pancetta into small pieces and sauté in a pan over medium heat until crispy. Remove from heat.
In a bowl, whisk egg yolks with grated Parmesan cheese and a pinch of salt until smooth.
Drain pasta, reserving some pasta water. Quickly toss spaghetti with the pancetta in the pan off heat.
Pour the egg and cheese mixture over pasta, stirring vigorously to create a creamy sauce. Add reserved pasta water a little at a time if needed to loosen the sauce.
Season generously with freshly cracked black pepper.
Plate by twirling spaghetti into a neat mound in the center of a shallow white plate.
Sprinkle additional crispy pancetta bits and grated Parmesan on top.
Finish with a few more cracks of black pepper before serving.