2 lbs. fava beans
One spring onion, diced
olive oil
1/2 c. minced green garlic
Chicken or vegetable stock
freshly ground pepper
Shell the Fava beans and parboil for 2 minutes.  Allow to cool and then pop the beans out of their skins.  Saute the onion in olive oil until quite soft, 10-15 minutes.  Add the green garlic, cook for 2 minutes more, and season well with salt.  Add the fava beans, cook for 2 more minutes, and then add just enough chicken or vegetable stock to cover.  Cook until the beans are tender.  Puree in a blender, adding additional stock until you reach the consistency you desire.  Cool the soup in an ice bath or your fridge, and season to taste with salt and pepper.
adapted from Chez Panisse Vegetables