Cook spaghetti in salted water according to package instructions. Remove the chorizo skins and cut the sausage into slices. Grate parmesan finely. Whisk eggs with 50 g Parmesan, season with salt and pepper. Wash parsley, shake dry and cut the leaves into fine strips.
Heat the oil in a frying pan and fry the chorizo in it while turning. Drain the spaghetti on a sieve, add it to the chorizo in the pan and stir-fry briefly.
Remove the pan from the heat, add the egg and parmesan mixture to the pan and mix into the hot spaghetti. The egg mixture should cook in the hot noodles, but not flocculate. Season the carbonara with salt and pepper, arrange in deep plates and sprinkle with parsley, remaining parmesan and ground pepper.