làu sā jīn dēui
流 is flowing and 沙 is sand. Together 流沙 is flowing sand or quicksand, referring to the runny custard. 煎堆 is sesame ball, so 流沙煎堆 is quicksand sesame ball.
Sesame balls) filled with molten custard.
sesame ball
lotus seed sesame ball
red bean sesame ball