Suan pan zi are commonly called abacus seeds, or abacus beads, from their resemblance to the counters on the calculating tool.
Connotations of prosperity make this a popular festival dish, especially during the Chinese New Year, but outside of private homes, you can't count on seeing it often, even in Singapore. Essentially, abacus seeds are dimpled gnocchi, made from boiled yam paste blended with tapioca flour; at Jin Ji Mei Shi they're fried with minced pork and dried mushrooms (S$2, about US$1.50 at the time).
Also: a half-and-half order of sweet potato and yam steamed "cakes" (S$2.00), cut from the rectangular pans shown at bottom.
Jin Ji Mei Shi
Maxwell Food Centre, stall 96, Singapore
Closed after lunch and all day Wednesday
(From a summer 2010 visit)