Wash the fava beans. Rinse the beans thoroughly under running water and drain well. You may notice a few black spots on the beans that do not wash off. This is perfectly normal.
Trim and cut the beans. Snap off the tips and trim the stem ends of the fava beans. You can remove the ends by hand or use a knife. Cut the beans into 1½-inch pieces.
Prepare the aromatics and herbs. Finely dice the onion. Slice half of the garlic cloves and crush the remaining cloves. Finely chop the cilantro, discarding the tough bottom stems.
Sauté the onion and garlic. Heat the olive oil in a large pot over medium heat. Add the diced onion and sauté until softened. Add the sliced garlic and stir briefly, then add half of the chopped cilantro. Stir everything together for about 20 seconds.
Add the fava beans. Add the beans, working in batches if necessary. Stir well to coat them with the onion, garlic, cilantro, and olive oil. Continue sautéing for about 8 minutes, until the beans have wilted considerably.
Add water and simmer. Pour in enough water to cook the beans, season with salt, and bring to a boil. Cover the pot, reduce the heat to low, and simmer for 35–40 minutes, or until the beans are tender.
Add the remaining garlic and cilantro. After the cooking time, you may notice that some of the liquid has evaporated. Add the crushed garlic and the remaining cilantro. Stir gently and cook for another minute to allow the flavors to meld.
Adjust the seasoning. Taste and add more salt if needed.
Serve and enjoy. Transfer the cooked fava beans to a shallow serving dish and drizzle with fresh lemon juice. Serve warm with Lebanese bread and, if desired, a side of plain yogurt.