1. First soak the shark fin in boiling water, and then scrape the sand off it with a knife; Trim off irregular edges and burrs at the same time. If the wings are old, they should be soaked and scraped twice repeatedly until the sand is clean.

2. Boil the cleaned shark fin in a cold water pot, add a little alkali, and cook for about an hour with slow fire. When you can pinch it with your hands, take it out of the pot (if you can't pinch it, you can continue cooking). Then rinse with water once or twice to remove alkaline odor.

3. Shark fin is an extremely precious seafood treasure. Chefs often mix shark fin with other raw materials with high nutritional value and full flavor when cooking, such as making soup, making soup and stewing meat. Or they can make it into braised chicken wings separately.