PProvenance
Enter
P
Japanese · Japan

Japanese Shiruko and Zenzai Sweet Adzuki Bean Soup and the Mochi Accompaniment Tradition

Shiruko and zenzai are closely related preparations built on sweetened adzuki beans served hot, each anchoring one of Japan's most enduring comfort food traditions. The terminology is region-specific and frequently misused: in the Kanto (Tokyo) region, shiruko refers to the smooth, fully puréed version (smooth adzuki soup) while zenzai refers to the chunky version with whole beans and visible texture. In Kansai (Osaka/Kyoto), the regional usage inverts: koshi-shiruko is the smooth version, tsubu-shiruko is the chunky, and 'zenzai' in Kansai specifically means the thick chunky bean paste served with only a small amount of liquid—nearly the texture of anko spread in a bowl. Both preparations are served with either grilled mochi (焼き餅, placed directly in the bowl) or shiratama dango (soft glutinous rice balls, cooked separately and added at serving). The mochi element provides the textural contrast and the ritual significance: the New Year grilled kagami mochi pieces are traditionally added to shiruko in a custom called kagami biraki (mirror opening), where the dried round mochi is broken (never cut—cutting implies severance) on the 11th of January and the pieces simmered or grilled into the sweet bean soup. Beyond seasonal ritual, shiruko and zenzai are year-round fixtures at wagashi cafes, traditional kissaten coffee shops, and at temple fair stalls, representing the deep integration of adzuki sweetness into Japanese daily comfort food culture.

ServesFour portions
Sourced0of 5 in BC
Cook
I

The Market List

The benchmark for each ingredient, and who stocks it near you. Tap a stockist to go straight to the product.

300 g
adzuki beans
dried, sorted and rinsed
Not yet stocked in British Columbia
120 g
caster sugar
added only after beans are fully tender
Your own market
1 pinch
fine sea salt
added at the finish
Your own market
For the shiratama dango
150 g
shiratamako (glutinous rice flour)
Not yet stocked in British Columbia
120 ml
cold water
added gradually until dough is soft and smooth
Your own market
II

The Method

1
Place the sorted, rinsed adzuki beans in a saucepan and cover generously with cold water. Bring to a full boil and cook for 5 minutes. Drain and discard this first cooking water entirely — this is the shibori step, removing the bitter saponins that would otherwise cloud and astringent the finished soup. The water poured away will be noticeably dark.
2
Return the drained beans to the pan and cover with fresh cold water by at least 5 cm. Bring to a gentle simmer and cook, partially covered, for 60–90 minutes, adding water as needed to keep the beans submerged. The dish lives or dies at this stage: the beans must be completely, unresistingly tender — press one between the fingers and it should collapse to a smooth paste with no grainy core — before any sugar is introduced. A bean with any firmness remaining will harden irreversibly once sugar is added, producing a grainy texture no subsequent cooking can correct.
3
For smooth shiruko (Kanto style): pass the fully cooked beans and their liquid through a fine-mesh tamis or drum sieve, pressing firmly to extract a silky purée. Discard the skins. Return the strained liquid and paste to a clean pan, add the sugar, and stir over low heat until the sugar is fully dissolved and the soup is cohesive and uniformly smooth. For chunky zenzai (Kanto style): retain the whole beans in their cooking liquid, add the sugar, and stir over low heat until dissolved and the beans are evenly glazed in the sweet liquor. In either case, the soup should coat a spoon lightly and appear a deep mahogany red.
4
Add a small pinch of fine sea salt to the finished soup and stir once. Taste: the salt should not be perceptible as such but should open the adzuki flavour and relieve any sense of monotonous sweetness. The soup is now complete. Keep warm over the lowest possible heat.
5
Combine the shiratamako with cold water added gradually, working the dough by hand until it is soft, smooth, and just barely non-sticky — the texture of an earlobe is the traditional test. Roll into balls of approximately 2 cm diameter. Drop into a pot of boiling water and cook until the balls rise to the surface, then continue for a further 1 minute. Remove with a slotted spoon and transfer immediately to cold water to arrest cooking. The dango are ready when firm to the touch on the outside but yielding within.
6
Ladle the hot adzuki soup into warmed bowls — lacquerware for ceremonial service. Drain the shiratama dango and place two or three in each bowl. Serve at once: the mochi provides the chewy, neutral textural counterpoint that defines the dish against the velvety bean medium.
III

Quality Hierarchy

01
Reserve — Dried adzuki beans sourced from Hokkaido's Tokachi region, the benchmark Japanese crop; unrefined wasanbon or light kurozato (black sugar) for layered sweetness; shiratamako ground from premium glutinous rice; service in antique urushi lacquerware over binchōtan-grilled kagami mochi for kagami biraki.
02
Estate — High-grade dried adzuki beans from a named Japanese or Taiwanese source; good-quality caster or light muscovado sugar; shiratamako from a specialist Japanese grocer; presentation in simple ceramic or wooden bowls.
03
Market — Dried adzuki beans from a well-stocked Asian supermarket; standard caster sugar; katakuriko-based shiratama mix acceptable. The full shibori and sato ga shimu method still applied — technique compensates for modest sourcing.
04
House — Tinned adzuki beans are a significant compromise; if used, drain, rinse thoroughly, and re-simmer before sweetening. Pre-made shiratama dango from refrigerated packets. The dish remains serviceable but loses the silky depth that slow bean cookery produces.
IV

Sensory Tests

◇Touch. A cooked bean pressed between the fingers collapses to a smooth, grain-free paste — the sign that sugar may safely be added.
◇Sight. The finished soup is a deep mahogany red and coats a spoon lightly without running off immediately.
◇Touch. Shiratama dango float to the surface of boiling water and, after one further minute, yield to gentle pressure without collapsing — firm outside, soft within.
◇Smell. The simmering adzuki soup carries a clean, earthy, subtly nutty aroma; any sharp or astringent note indicates the shibori was insufficient and the first water should have been discarded more decisively.
◇Where it lives or dies. The beans must reach complete, unresisting tenderness before sugar is added — any residual firmness at this point will harden irreversibly once the sugar enters the pan, producing grainy beans no further cooking can correct.
Pillar V
Cross-cuisine parallels are part of membership.
The dishes this one teaches you, across the cuisines — on every recipe.
Enter · from $49 a year
VI

What to Pour

The pairing
Nikka From The Barrel
Nikka Whisky — Miyagikyo Distillery · Miyagikyo — Nikka Distillery
Not yet stocked in British Columbia
Whisky
From British Columbia

Nothing from British Columbia holds against this yet.

Without alcohol

No pour without alcohol holds against this yet.

Why each one works is part of membership — Enter · from $49 a year →

The whole pairing
Pillar VII
Origin and lineage are part of membership.
Where the dish comes from and how it came to be — on every recipe.
Enter · from $49 a year