Using a soup spoon, place rounded spoonfuls of the dough over the fruit, forming small dumplings. Sprinkle the dumplings with the cinnamon sugar, to taste. Tightly cover the skillet with a lid or a sheet of foil and steam the mixture over medium-low heat, without opening the lid, until the dumplings are set and puffed and the surface is dry when touched, about 15 minutes.