Ingredients required for sweet and sour pork loin: half a pound of pork ribs, 1 carrot section, 3-4 tablespoons of tomato paste, appropriate amount of oil and salt, 1 section of green onion, 1 slice of ginger, 1 tablespoon of light soy sauce, 1 cooking wine tablespoon, half teaspoon of white pepper, 4 tablespoons of white sugar, 2 tablespoons of rice vinegar, 5-6 tablespoons of starch, steps: 1. Use pork ribs, the meat is tender. Cut the tenderloin into 1cm thick slices first, then into 1cm thick strips. 2. Put the tenderloin strips into a large bowl, add a little salt, white pepper, light soy sauce, cooking wine, grab it with your hands, mix the seasonings evenly, grab the meat strips firmly and make them sticky, and marinate for 10 minutes. 3. Prepare the seasoning, cut the onions and ginger into cubes, and cut the carrots into strips. 4. Add starch and 1 tablespoon oil to the marinated meat strips. 5. While grasping with your hands, pour in an appropriate amount of water. The paste should not be too thin. Grasp and mix the paste thoroughly so that each meat strip is coated with a layer of starch paste. 6. Add oil to the pot and heat until it is about 60-70% hot. Add the meat strips one by one into the oil pan and fry until the meat strips are set. Remove the meat strips and set aside. If there is not much oil, fry the meat strips in two batches. If there is less oil and more meat, the oil temperature will not rise, and the meat strips will easily stick together. 7. Increase the oil temperature in the pot to 70-80% hot, add the meat strips and fry again until the meat strips are golden in color, crispy on the outside and tender on the inside. Remove the meat strips, drain the oil and set aside. Place the carrot strips into the oil pan and drain immediately. Drain the oil and set aside. When re-frying the meat strips, do not fry them for too long. If the frying time is too long, the meat will become hard and not tender when eaten. 8. Pour out the oil in the pot, leaving a little base oil, add tomato paste, sugar, rice vinegar, and a little salt, stir-fry over low heat, and stir constantly with a spoon to prevent the bottom of the pot from sticking. 9. When the sauce becomes thickened, add the onion and ginger, a little water starch, and stir evenly. 10. Add the fried meat strips and carrot strips, stir-fry quickly over high heat evenly, remove and serve on a plate.