Archaic interjection of praise, originally from Chinese; rarely used in modern Japanese outside of historical or literary contexts.
In classical texts, there are scenes where someone is praised with 'Zenzai, zenzai.'
zenzai; sweet red bean soup
A traditional Japanese dessert soup made with azuki beans, often served with mochi or shiratama. Usually written in kana.
On cold days, I crave warm zenzai.
Kanji form is uncommon in modern usage; mainly seen in classical contexts or as a stylistic choice.
The interjection sense comes from Chinese 善哉 (shànzāi), an exclamation of praise. The food sense is said to derive from the interjection, possibly because the soup was considered so delicious it elicited praise, but the exact connection is uncertain.