Cut the tiptoe of the chicken feet off. Then combine chicken feet with spring onion roots and several pieces of ginger slices. Cook for around 10 minutes after the water becomes to boil.
Put the chicken feet in cold water to cool down.
Mix the ingredients to make the sweet and sour sauce.
Soak the cooked chicken feet in sweet and sour sauce in a sealed container and then place the container in refrigerator for around 8 hours.