Custard Bun 奶黃包 (9)A fluffy soft bun filled with a golden decadent filling. Chinese steamed custard bun is a type of bao, bun or bread with a custard filling. Custard bun also called nai wong bao () which is yellow milk bun. In addition, its originated from southern China and very popular Cantonese dim sum item that you can find at most of Chinese dim sum restaurants. Often, custard buns are eaten for breakfast or as a snack. It is a kind of bread that is steam cooked