Sarara is one of the most consistently respected soup curry restaurants in a city that takes soup curry seriously. The broth is built over several days and has the depth of a long-cooked stock with the layered spice of a good curry — aromatic rather than simply hot, with a complexity that cheap soup curry places don't achieve. You customise the spice level when ordering, and the standard choices of chicken leg, lamb, or vegetables all come with large pieces that require a spoon rather than chopsticks. The chicken leg in soup is the classic preparation; the bone falls away cleanly.
Soup curry is a Sapporo invention from the 1970s, developed at a few small restaurants that experimented with making curry broth rather than curry sauce. Sarara sits in the Susukino district, which means it's busy at dinner and tends to fill by 7pm. The interior is small and the service brisk — this is a neighbourhood restaurant that happens to be good rather than a tourist-facing operation. Worth seeking out over the more heavily promoted chains.