In authentic Italian cooking there is no chicken carbonara, but even in Rome there are restaurants that prepare the pasta carbonara in a wrong way. First of all the use of guanciale is very important, which you can always replace with pancetta. More important than this it is already such a rich dish that it does not need butter or cream. Of course you can prepare whatever you like and call it as you want, but if you want to eat as a Roman, here the authentic recipe. When in Rome often the best carbonara is eaten outside the city, like in the area of the so called Colli Albani, where they produce an excellent guanciale. This because unfortunately the center of Rome is full of tourist traps, that serve carbonara prepared with bacon and cream.
6 oz of spaghetti, 3 oz guanciale, one small onion, half glass of dry white wine, half a cup of pecorino cheese, one egg, salt pepper, one teaspoon olive oil
Fry the guanciale at medium high heat. It has to get crunchy! Low the heat add the chopped onion. When the onion is cooked add the wine which you make evaporate at low heat. Mix the egg the cheese the pepper and the oil in a large serving bowl. When the spaghetti are al dente pass them in the pan with the warm bacon for one minute at medium heat. Than pour everything into the bowl and mix until the egg and cheese get creamy.