Legend has it that on a rainy day, Huang Zhangma, who runs a small noodle stall called "Cape Hotel" at the ferry pier, kept putting the marinated eggs back into the pot because of poor business, because the marinated eggs kept blowing, and the less marinated they were, the darker the color was. To our surprise, the guests like this kind of food. The title is "Grandma's Hard-to-find Iron Eggs", and the report has attracted many people's attention. Some media even came from Japan to interview them. Since then, iron eggs have become a famous snack in Danshui.
After Grandma Huang Zhangma became famous for her iron eggs, she produced a large number of iron eggs for merchants to sell in batches. Yang Biyun was one of the shippers of that year. Later, he introduced his own production technology and first applied for the registered trademark of "Grandma's Iron Egg". In the future, she became the ancestor shop of Iron Egg, which is the famous "Grandma's Iron Egg" in the old street.