Sayur asem is a sweet and sour vegetable soup. Often referred to as tamarind soup, it is one of the favorite vegetable dishes in Indonesia. The entire dish is based on tamarind, an unusual plant commonly grown in Southeast Asia, which gives the dish a distinctive sour taste.

Other traditional Indonesian ingredients in sayur asem include jackfruit, melinjo, long beans, bilimbi, pumpkin, corn, and chayote. Sayur asem originated among the Sundanese people residing in West Java. However, their original recipe for this traditional soup has been adapted across Indonesia.

Employing the available ingredients, numerous different varieties of sayur asem have been created. Usually, these newly formed varieties were named after a region of their origin. This soup is extremely versatile and can be served as an appetizer, first course, or a side dish with the main meal.

Most commonly it is served alongside rice, fried chicken, tempeh, tofu, and fried or salted fish. It is traditionally prepared during summer, when it is typically served warm.