Bring a large pot of water to the boil. Season lightly with salt.
In a large bowl, whisk together the whole eggs, egg yolks, grated pecorino and plenty of freshly ground black pepper. Set aside.
Place the guanciale in a cold frying pan over medium heat. Cook gently until the fat has rendered and the guanciale is golden. Turn off the heat.
Cook the pasta until al dente.
Using tongs, transfer the pasta directly from the pot into the pan with the guanciale, allowing some pasta water to come with it. Toss to coat in the rendered fat. Remove the pan from the heat and let it sit for about 1 minute.
Add the egg mixture and ½ cup (125 ml) hot pasta water. Toss vigorously until the sauce becomes glossy and coats the pasta.
Add more pasta water, a little at a time, until the sauce is silky and evenly coats the pasta.
Taste and adjust with extra pecorino or black pepper if needed. Serve immediately.