Bigoli alla carbonara

Servings 4
    500g / 1lb Bigoli
    5 oz guanciale (or bacon)
    1 finely chopped onion 
    4 egg
    3 ½ oz Pecorino cheese or Parmigiano
    3 spoons of chopped parsley (optional)
salt and pepper to taste

Cook the Bigoli in a large pot of salted water.  
Meanwhile, cut the pancetta or guanciale into strips and put it in a large pan.  Gently brown the pancetta or guanciale, then add the onions and brown the onions.
Next, beat the egg yolks with the Pecorino cheese, and add two spoons of milk or cream, and grind some black pepper in.
When the pasta is cooked al dente, drain it and put it into the pan with the bacon.  Empty the pasta/bacon/onions from pan into a mixing bowl and add the beaten egg yolk mixture and the chopped parsley; finally, add a tablespoon or two of the pasta's water from cooking it for a creamy result.
Serve the pasta immediately and grate a little more of the Pecorino cheese on top for presentation.