Japan — zōsui tradition from Heian period as a poverty food (stretch leftover rice with broth); elevated to a prized nabe ending dish during the Edo period when nabe culture became a social institution
Zōsui (雑炊 — 'miscellaneous cook') is a comforting rice-in-broth dish that is fundamentally different from okayu (rice porridge) in its starting point and result. Okayu is made from raw or soaked rice cooked in a large quantity of water from the beginning. Zōsui is made from previously cooked rice added to a flavoured broth — typically the remaining broth from a nabe (hot pot) at the end of a meal. The cooked rice grains are rinsed briefly in warm water before adding (to remove surface starch that would over-thicken the soup), then simmered gently in the broth until the rice swells and absorbs the surrounding liquid. The result should be rice grains that are distinct, slightly swollen, and tender — surrounded by a light, flavourful broth that carries all the accumulated umami from the nabe. An egg beaten and drizzled into the simmering zōsui creates a silken egg-ribbon effect (tamago-toji). Garnishes include sliced green onion, mitsuba, and crumbled nori. Zōsui is the meal's natural ending point when sharing nabe — the entire table participates in deciding when to transition from the nabe to the zōsui, and the host prepares it at the table in the same donabe or nabe pot.
Clean, concentrated broth from the nabe surrounding swollen, tender rice grains; egg ribbons add richness and protein; the flavour is the accumulated umami of the entire meal's cooking — a distillation of what came before
{"Cooked rice is rinsed before adding to remove excess surface starch — otherwise the broth becomes overly thick and gluey","The broth must be flavourful before the rice is added — zōsui relies entirely on the accumulated dashi and ingredient flavours of the nabe","Simmer gently until rice swells (5–8 minutes) — do not boil vigorously; this breaks the already-cooked rice grains","Egg addition (tamago-toji) is optional but classic — beaten egg drizzled in a thin stream while stirring creates silken ribbons","The transition from nabe to zōsui is a social ritual — the table collectively finishes the nabe ingredients before zōsui is begun"}
{"Shabu-shabu zōsui: the accumulated sesame and ponzu flavours in the broth create an extraordinary finishing bowl","Sukiyaki zōsui: the sweet-savoury warishita-flavoured broth produces an intensely satisfying, slightly sweet zōsui","Egg temperature: beat the egg to room temperature before drizzling — cold egg causes uneven cooking and clumping","Mitsuba garnish is traditional — add after cooking is complete, as the residual heat gently wilts it to a perfect soft-herb finish"}
{"Using rice directly from the pot without rinsing — excess starch creates a gluey, opaque soup rather than a clear, flavourful rice-broth","Adding too much rice — zōsui should have rice floating in broth, not broth in a mass of rice; err on the side of less rice","Boiling vigorously after adding rice — breaks the rice grains and creates a mushy porridge rather than distinct, swollen grains in clear broth","Making zōsui from plain, unseasoned water — it is entirely dependent on the existing broth; a poor nabe broth produces a poor zōsui"}
Japanese Country Cooking (Celine Rich) / Japanese Cooking: A Simple Art (Shizuo Tsuji)