Bao, also known as baozi, is a type of filled bun or bread-like dumpling that originates from Chinese cuisines. It is a soft, fluffy dough thats steamed with various fillings inside. The fillings vary widely, from savory meat fillings to sweet custard ones. Bao is a variation of mantou from Northern China. The dough is made with flour, yeast, sugar, baking powder, milk, and oil, and is slightly sweeter than dumplings. Bao can be served as a doughy closed bun wrapped around the filling and pinched at the top, or as an open-faced "gua boa," which is a flat, lotus-leaf style bun that folds over the filling.

Bao fillings tend to be savory, balancing out the sweetness in bao dough. Pork is one of the most common ingredients resting inside the fluffy buns, sometimes pork belly but more often barbecue-style pork, appearing on menus as cha siu bao. Other fillings include beef, fish, glazed mushrooms, and pickled vegetables. Bao is a popular street food in many Asian countries, and it is also increasingly appearing on fine-dining menus across Asia, Europe, and beyond.

In summary, bao is a type of filled bun or bread-like dumpling that originates from Chinese cuisines. It is a soft, fluffy dough thats steamed with various fillings inside, and it can be served as a doughy closed bun or an open-faced "gua boa." Bao fillings tend to be savory, and pork is one of the most common ingredients.