Oil your hands, pinch a small piece (about the size of a ping pong) of the dough and roll it into a ball. Flatten the ball on your palm and place a tablespoon of the filling on the center of it. To make light dumplings, flatten the dough out as much as possible. Wrap the edges around the filling and pinch them together to seal, then gently roll it into a ball. Place the dumplings on the greased tray and repeat with the rest of the dough.