1. Place half of the tapioca starch in bowl with the salt and add the boiling water.
2. Mix the ingredients with a wooden spoon, it will cool slightly.
3. When it is comfortable to touch, add the rest of the tapioca and knead the dough with your hands.
4. The dough is ready when it is soft and no longer sticky.
5. Wrap the ball of dough in a piece of plastic wrap to keep it from drying out.
6. When you are ready to fill, take a small piece of dough and shape it into a ball.
7. Using the thumbs, press the ball while rotating in a circular motion forming a disc about 2 ½ inches wide.
8. Place a small amount of filling into the center of the disc and fold the dough over so the two sides touch, forming a half circle. Pinch shut.
9. Heat up salted water in a large pot. When the water is boiling, add the dumplings and cook for 10 – 12 minutes, at this point the dumplings will float to the top.
10. Drain the dumplings, then toss in the onion oil to keep the dumplings from sticking to each other.