The easiest to cook and delicious recipe of lettuce is known as lettuce soup. The main ingredients of lettuce soup is usually wasted lettuceâ€™s outer leaves and lettuceâ€™s ribs. Moreover, with lettuceâ€™s leaves you can also add some spinach, arugula, watercress and some potatoes. In addition to these, the other ingredients used in lettuce soup are finely chopped white onions, lettuce broken into small piece, pint water, vegetable oil, Plain yoghurt and salt to taste. It is considered that using the iceberg is the best way to give a strong flavour to the soup.