Bánh bao

Bánh bao is a Vietnamese bun based on the Cantonese tai pao or da bao (large bun), which was introduced to Vietnam by Chinese immigrants. It is a ball-shaped bun containing pork or chicken meat, onions, eggs, mushrooms and vegetables, in Vietnamese cuisine. It often has Chinese sausage and a portion of a hard-boiled egg inside. They are filled with savory fillings, the most common being seasoned ground pork and quail egg. A vegetarian version of bánh bao also exists.

Source: Wikipedia