First, flush the trachea of the pig's lungs with a faucet. After the pig's lungs swell, use foam to squeeze out blood, and repeat until there is no foam. Step 2: Boil the washed pig lungs in a pot for two minutes, take them out and wash them with cold water, then squeeze the lungs to see if there is foam. Clean and cut into small pieces. Third, remove the small stems of kumquat, wash them, and then cool them to dry. Dry kumquat in rice cooker to make kumquat skin dry and soft. Then cut the bottom of kumquat into crosses with a knife. Finally, put the pork lungs and kumquat into the rice cooker to make soup.