What's the name of that black diamond cake in Guangxi?

Water chestnut cake. According to public information, horseshoe is a famous specialty in Guangxi, and it is also called the four dessert specialties in Guangxi with lotus root powder, betel nut powder and lily powder. Most of them are black diamonds, which are used to make cakes. The meaning is very auspicious, and it means "one step at a time, rising year after year".