The pastry of the Dragon Ball biscuits is believed to be invented in Bukit Tambun, Penang, hence known as Tambun Piah/biscuits. It is made from both water and oil dough, hence thicker and less flaky than the original tau sar pniah.
The difference between the two biscuits: Tau Sar Piah – bigger, softer in texture, has a thinner crust and is crumblier, while the fillings come in either sweet or savoury and they are mostly wrapped in paper.
As for tambun piah or a dragon pearl/ball, it is smaller in size, with a thicker crust (made from both water and oil dough), has a sweet paste and is wrapped in boxes.