Heat a frying pan until hot. Add the olive oil and pancetta and cook for 3-5 minutes, or until crisp. Remove the pancetta from the pan and set aside to drain on kitchen paper.
Whisk the egg yolks, parmesan and cream in a bowl and season, to taste, with salt and freshly ground black pepper.
Cook the penne according to pack instructions in a pan of salted boiling water.
Drain the pasta and add it to the cream mixture, stirring continuously until smooth. Add the pancetta and parsley and stir until well combined.
To serve, spoon pasta into warmed bowls and sprinkle with a little extra parmesan.