Finely chop the onion
In a pan, add extra virgin olive oil and brown the onion.
When the onion is brown, add the rice and toast it for a couple of minutes.
Blend the toasted rice with the white wine. I suggest you use the one you will drink during the meal.
When the wine is evaporated, add part of the vegetable broth. Heat is medium-low.
While the rice is slowly cooking, start cooking the fava beans in a small pan. If the cooking time is 10 minutes, just cook them for 5 minutes, since they will finish coooking mixed with the rice.
After 5 minutes, take half of the fava beans and make a cream adding some water and using a mixer.
Add the remaining fava beans to the rice and go on cooking them, slowly adding the broth.
In the meanwhile, use a small pan and some butter to fry the ham cut into small stripes.
Add the fava bean cream and keep on cooking, gently mixing from time to time. Always add the broth in small amounts, so you can control the rice cooking.
Last minutes of cooking for the rice.
When it's almost done (at this point broth should be absorbed), turn off the heat, add the butter in this slices and the grated Parmigiano Reggiano. Mix with a spoon and cover the pan. This phase is called "mantecatura" in Italian.
After 5 minutes the rice is creamy and ready. You can serve it adding some fried ham on top... and buon appetito!