Start by bringing water to a boil for the fava beans and cook them for 30 minutes.
Finely chop the onion, place it in a pot with a drizzle of extra virgin olive oil, and let it soften for a couple of minutes. Add the fava beans and cook everything together for about 10 minutes. Once cooked, set them aside.
Meanwhile, cook the pasta in plenty of boiling water. Grate the pecorino and place it in a bowl, then add a drizzle of extra virgin olive oil, a pinch of pepper, and a ladle of the pasta cooking water. Mix well to create a smooth cream.
When the pasta is cooked, drain it and add it to the bowl with the pecorino cream. Toss everything together, then add the fava beans. Serve with a generous sprinkle of freshly grated pecorino.