Manathakali keerai thani saaru, also known as black nightshade thanni saaru, is a traditional South Indian soup made with black nightshade leaves. This nutritious and flavorful dish is packed with vitamins and minerals. The saaru has a tangy and slightly spicy taste, making it a perfect accompaniment to rice or as a light soup. It is easy to prepare and can be enjoyed as a comforting and healthy meal.