1. Cut off tops of tomatoes with stems (this will make nice lids). Scoop out the insides of tomato using a teaspoon and small knife. Turn them upside down to drain juice.
2. Using a fork or a hand held blender, mash fava beans with the rest of the ingredients, leaving a few chunks. Salt and pepper, to taste.
3. Fill tomatoes with the filling and serve on lettuce leaves.
Source of recipe: Once I had something like this and made up this recipe.