The small, normally rust-colored beans of the vine Vigna angularis, which grows throughout East Asia as far as the foothills of the Himalaya Mountains, has several culinary uses but is most commonly cooked and preserved as a sweet paste. This red bean paste is one of the more popular fillings in bakery breads and confectionery treats. It is most often used in breads and biscuits, though it's found in a variety of other foods.
Believed to have been first cultivated as early as 1,000 B.C., it is a nutritious staple starch. In Japan, where the bean is named azuki, its consumption is second only to the ubiquitous soybean. In Chinese cuisine, the common name for this bean, as well as the red bean paste, is dousha, and Koreans call it pat. Elsewhere in Asia such as India, they may bear the translation “red cowpeas.” The red bean is rich in carbohydrates, proteins, soluble fiber and mineral iron.
Sweet red bean paste is very simply made by boiling dried azuki beans in sugared water, sometimes in honey with additional flavorings such as ground chestnut. Left whole in the resulting syrup, it can be eaten as is or used in various ways, such as either a hot or cold dessert soup. The cooked beans are more commonly mashed into a more easily spread paste consistency. In Japan, this red bean paste is called an. The husks of the bean can be further removed with a sieve such as cheesecloth for a creamier, almost jam-like texture.
Many Asian cultures use this red bean paste as a filling or topping for a variety of baked breads and pastries. Anpan is a baked Japanese savory bread filled with sweet bean paste; Korean chalboribbang is a thin, bean paste sandwich of sweet barley flour pancakes. The Chinese leavened and steamed bread baozi’s most popular fillings are barbecue pork and red bean paste. Different regions throughout east Asia have their own unique variation of the thin-crusted and generously filled pastry called mooncakes.
Other vehicles for red bean paste include firm biscuits and gelatinous rice pounded to a chewy soft mozzarella cheese consistency. Less common confections include its use as a topping for shaved ice and its mixture with agar into a firm gel. n Japan, the azuki beans are sometimes incorporated into legume dishes, such as sekihan — a simple mix of rice and beans traditionally served for special celebratory occasions.