Sweet Stuffed Pancakes from West Sumatra

At most martabak stalls, whether on the alun-alun in Yogyakarta, or on a street corner in Padang, the savoury martabak vendor will also sell sweet martabak; or, if he has only one skillet and is limited to one sort, a colleague, friend, or relative next door is selling the other. The recipe below is based on notes I made when we ate this sweet martabak in Padang. There, they call it Martabak Kubang, because that particular group of martabak sellers is from a village of that name nearby. If