They can be eaten at any meal in Chinese culture, and are often served in restaurants that have dim sum service. The xiao long bao is also popular when eating jiaozi or with Shanghai La mian.
To eat these, peel the dumpling off the lettuce or cabbage leaf taking care not to break the dumpling skin and deposit it into a Chinese soup spoon, which is usually provided, adding the vinegar provided as desired. Some places may also have shredded ginger. Take a small bite of the skin, allowing some of the broth to drain, and drink a bit of it. Then eat the rest of the dumpling from the spoon. Doing so will allow you to savor the taste without scalding the tongue.

Sheng Jian Bao is like a bao zi in that it has a meaty filling inside roughly shaped like a xiao long bao but pan fried. Its origins are from Shanghai.
Char
Siu Bao, a.k.a Chinese Barbecue Pork
Buns, are fluffy, white buns that are
commonly served at Chinese restaurants
during dim sum. At their best, Char Siu
Bao are soft as a pillow and filled with
a savory mixture of minced Chinese
barbecue pork (char siu), soy sauce,
oyster sauce, scallions and sugar.