Remove the sausages from the skins. Using wet hands, roll the sausage into small balls about the size of marbles. Set aside.

Heat the olive oil in a large pan over medium heat. Add the sausage balls and cook until they are starting to brown, then add the bacon. Continue to cook until the sausage and bacon are both cooked through.

While the sausage is cooking, bring a large pot of salted water to a boil. Add the pasta and cook until al dente. Reserve a mug full of the pasta water before draining.

Combine the egg yolks, cream, Parmesan, lemon zest and parsley in a bowl and whisk to combine. Immediately after draining the pasta, return it to the same pot and add the egg yolk mixture. Vigorously stir the pasta and the sauce - the heat from the pasta will gently cook the eggs. It should form a silky sauce after stirring for a minute or two. If the sauce becomes too dry or stiff, add a bit of the reserved pasta water to loosen it up.

Stir the sausage and bacon into the pasta. Season to taste with salt and pepper. Drizzle each serving with olive oil before serving.