Hot and sour soup is a popular example of Chinese cuisine. Although it is often said to have originated in Sichuan, this is actually a variant of hulatang or "pepper hot soup" (Chinese: 胡辣汤) with added vinegar to enhance the sourness. This variation is found Henan cuisine. Also popular in Southeast Asia, India, Pakistan and the United States, it is a flexible soup which allows ingredients to be substituted or added depending on availability. For example, the American-Chinese version can be thicker as it commonly includes corn starch, while in Japan, sake is often added.