Use a mortar and pestle to grind the peppercorns to a coarse powder. Scoop out into a large bowl. Crack in the eggs, then add the egg yolks and parmesan. Whisk until well combined. Heat the guanciale in a large frying pan over high heat (you don’t need any oil initally). You want the pork to colour as well as render some fat. If there isn’t a sheen of fat on the bottom of your pan after 3-4 minutes, then add the olive oil. Turn the heat off but let the pan sit on the warm stovetop. Bring a large pot of water to the boil. Cook or soak the noodles for their recommended cooking time. Reserve a cup of noodle cooking/soaking water. Then drain the noodles and add them straight into the warm pan. Add the egg mixture and toss with the noodles. Keep tossing the noodles in the egg mixture until it thickens (turn the heat on low under the pan if necessary – just be careful not to scramble the eggs!). If the sauce becomes too thick, you can loosen it with some of the pasta cooking water. When the sauce is thick, divide among serving plates. Sprinkle over extra pepper if required and serve immediately.