Siu haau is a popular type of thick, savory, and slightly spicy barbecue sauce that is primarily used in Chinese and Cantonese cuisine. It is not used as a flavoring after the food is done, like some other sauces, but during the barbecue process, while the meat is still cooking.

The sauce usually consists of a combination of soy, oyster, and hoisin sauce, sugar, garlic, honey, pepper, and salt.