1. Bring a large pan of water to the boil, salt it well and throw in the pasta.
2. While the pasta cooks, put the parmesan, egg yolks and cream into a very large bowl. Season and whisk together.
3. As soon as the pasta is cooked, drain it, then tip it into the bowl. Add the ham and quickly toss everything together using two forks. The egg will be cooked by the heat of the pasta, and the creamy sauce will cling to the strands. Serve straight away, with more grated parmesan if you like.