Soak the moong beans in water for 30 minutes; drain. Roll the kaffir leaves into thin cigarettes; slice into slivers. In a mortar pound the drained moong beans to form a paste. Add the other ingredients in turn, stirring well. Pluck a small piece of the paste and form into a ball the size of a walnut. Do not mould too tightly. Deep-fry the balls until golden brown, drain and serve with the thick sweet sauce below.
The Sauce: Gently heat the three ingredients until the sugar dissolves. Allow to cool before serving.
