Hong dou tang is a popular Chinese dish served in Mainland China, and Taiwan. It is categorized as a tang shui 糖水 or sweet soup. It is often served cold during the summer, and hot in the winter. Leftover red bean soup can also be frozen to make ice pops and is a popular dessert. A similar dessert 紅豆沙 in Hong Kong is commonly mistaken by people outside Hong Kong as the same dessert, of which the latter one has a very different texture.
In Cantonese cuisine, a red bean soup made from rock sugar, sun-dried tangerine peels, and lotus seeds is commonly served as a dessert at the end of a restaurant or banquet meal. Common variations include the addition of ingredients such as sago (西米, pinyin: xī mi), tapioca, coconut milk, ice cream, glutinous rice balls, or purple rice. The two types of sugar used interchangeably are rock sugar and sliced sugar (片糖).