Put the guanciale batons in a cold large skillet, then set over medium‑low heat. Cook, stirring occasionally, until the fat renders out and the meat is golden and crisp, about 10–12 minutes. Ensure the internal temperature reaches at least 145°F (63°C) for safety. Do not let it burn. Turn off the heat and reserve the guanciale and melted fat in the pan.

Bring a large pot of generously salted water to a rolling boil. Cook the spaghetti 1 minute less than the package instructions for al dente. Right before draining, reserve 2 cups of the starchy pasta water.

In a large heatproof bowl, whisk together the whole eggs, egg yolks, 1½ cups Pecorino, and the 1½ tsp of black pepper until thick and smooth. It will be paste‑like – that’s perfect. Place the bowl over a pot of gently simmering water (double boiler), whisking constantly, until the mixture reaches 160°F (71°C). Immediately remove from heat and set aside.

Drain the hot pasta (reserve the pasta water) and quickly add it to the skillet with the guanciale and its rendered fat. Toss with tongs over no heat until every strand is coated and the pan has slightly cooled – it should stop sizzling audibly.

Add the hot egg mixture to the skillet with the pasta and guanciale. Toss vigorously and continuously with tongs, adding splashes of hot pasta water as needed, until a glossy, creamy sauce coats each strand. Do not return to direct heat.

Plate the carbonara in warm bowls, shower with extra Pecorino and a generous crack of black pepper. Eat straight away while it’s voluptuous and hot.