Cooking soup with tomatoes, the sour appetizing taste can make people open their taste buds in a hot summer and increase their appetite. The easiest way is tomato egg drop soup or tomato fried egg soup. A little more complicated can be made into tomato and winter melon soup, plus a little meatball, which is twice as delicious! In fact, the best food is tomato gravy, sour and appetizing tomato soup, and crystal-clear and tender meat slices, which are delicious and invincible ~ ~ The two most important points for making tomato gravy: First, tomatoes should be cooked for a long time and have a strong taste; The second is to use sweet potato starch and cook it on low heat, so that the smooth meat will have a crystal clear outer layer. In fact, it is very important to add chopped green onion to tomato soup, and the taste is very different with or without chopped green onion.