Yōkan

Yōkan is a wagashi made of red bean paste, agar, and sugar. It is usually sold in a block form, and eaten in slices. There are two main types: neri yōkan and mizu yōkan. Mizu means "water", and indicates that it is made with more water than usual. Mizu yōkan is usually chilled and eaten in the summer, however in Fukui prefecture it is customarily eaten in winter. Although yōkan found in Japan and abroad is typically made with red bean paste, yōkan made from white kidney bean paste (しろあん, 白餡, shiro an) is also relatively common. This type of yōkan is milky and translucent with a much milder flavour than that made of red bean paste. As such, it can be effectively flavoured and coloured by using green tea powder.

Source: Wikipedia