Fettuccine with Fava Beans

3 1/ 2 pounds unshelled fava beans (about 3 very full cups) (1.575 kg) or 1 pound frozen fava beans (450 g)
6 tablespoons extra virgin olive oil
4 or 5 sliced scallions, white part only (about 1/ 2 cup)
Salt
1/ 4 pound boiled ham, coarsely chopped (115 g)
1 large clove of garlic
2 tablespoons chopped fresh mint
Freshly ground black pepper
2/ 3 pound dried fettuccine (300 g)
3 tablespoons freshly grated pecorino Romano cheese

Shell the fava beans if they are fresh, rinse in cold water, and drain. If they are frozen, thaw and drain.
Heat the olive oil in a large skillet. Add the scallions and cook over low heat for about 8 minutes, until they are meltingly soft. As they cook, salt them lightly and add a tablespoon of hot water occasionally to prevent browning. Stir every now and then.
Add the fava beans and ¡¿‹ cup (80 ml) hot water to the scallions. Cover the pan and cook for another 8 minutes over moderately low heat, stirring every now and then. Add the ham and cook 3 or 4 minutes longer, until the beans are tender but firm.
Finely chop together the garlic and mint. Add to the skillet and simmer for another 2 or 3 minutes. Season with salt and pepper to taste.
Cook the fettuccine in a large pot of boiling salted water until it is al dente. Drain the pasta and add to the skillet with the hot fava beans; mix well. Sprinkle the pecorino Romano cheese over the pasta, toss again, and serve at once on a heated platter, decorated with mint leaves. Pass extra pecorino Romano and a pepper mill at the table.
NOTE: If desired, pancetta can be used instead of the boiled ham. Chop it coarsely and cook with the onions over low heat until the onions are soft and translucent and the pancetta is light brown. Cook the fava beans until they are tender but firm, then follow the rest of the recipe.