In a large pot bring water to a boil on high heat adding a generous amount of salt. Add the pasta, stirring occasionally so as not to stick and cook according to suggested time on the box of the pasta less 1½’. Reserve 1 cup of cooking water.

In the meantime, in a large and deep pan over medium heat we add the olive oil and toss in onions along with a splash of water. Cook for about 3’ and add the prosciutto and fry for about 5’. Season with the salt and pepper and remove from the heat. Keep aside in the pan.

While cooking the prosciutto, take a medium bowl and lightly beat the eggs along with grated parmesan to create a smooth cream.

Strain the pasta and return to the pan with the prosciutto, which is set on very low fire and cook for another a minute. Remove from fire, add ½ cup of the reserved pasta water and toss to cool a bit, while stirring add the eggs/cheese mixture, stirring for further 30’’ so as the pasta absorbs the sauce. Add more from the reserved water if required.

Serve in individual plates, sprinkle some of the parsley, add some more grated parmesan and a crack of freshly cracked black pepper.