I love Carbonara, anything which also has cheese and ham or bacon in it, mmmm :) Best one was a seasonal dish at a cafe on the side of Lake Como.
Love spaghetti bolognese and simple pasta with fresh tomato sauce and herbs, had the most gorgeous one in Little Italy in New York, simple but delicious.
I have to say, the proper authentic stuff is so different. I lived with 3 guys from Sardinia for a while and the food they cooked was just amazing and very different to the italian food in restaurants over here.