Remove the roots of lotus root, peel it, wash it and cut it into pieces. Wash the corn and cut it into thick slices; Cut the pork ribs into pieces and wash them with clean water. Put them in a cold water pot and boil them together in boiling water; After blanching the pork ribs, rinse them with warm water and place them in a pot (pressure cooker, clay pot, rice cooker). Put the lotus root and corn into the pot together; Remove the foam and impurities from the water that blanched the pork ribs just now, and pour it into the stew pot. If the soup is not enough, add an appropriate amount of water to cover the pork ribs and corn. Boil for about 40 minutes.