How to Make It
Snap off and discard stem ends from fava bean pods; peel off and discard stringy seams on either side of pods. Split open pods, and remove beans.
Bring a medium saucepan filled with water to a boil over medium-high. Prepare an ice bath in a large bowl. Add beans to boiling water, and boil until tender, 2 to 3 minutes. Immediately transfer beans to ice bath, and let stand 2 minutes. Drain. Using your fingernail, tear or break through outer shell, and pinch out bright green beans inside. Discard shells.
Using a marble mortar and wooden pestle, grind 2 tablespoons mint, lemon zest, and salt into a smooth paste, about 30 seconds. Add half of the fava beans and 1/2 cup cheese. Pound and smash to a very coarse paste, about 5 minutes. Add remaining half of fava beans, and smash to a chunky spread. Stir in lemon juice, oil, and pepper. Taste and adjust seasonings.
Spoon fava spread on toasted bread slices. Top evenly with remaining cheese and remaining 1 tablespoon mint. Drizzle with oil, sprinkle with pepper, and serve.
Frozen edamame or English peas may be substituted for the fava beans.