Biriya is a distinctly Maithil preparation built around dried chickpea greens — the tender tops of the gram plant, sun-dried and dusted with a little flour into small pods that store through the year. Cooked into tarkari, the pods are lightly fried, then simmered with potato in a gravy of mustard paste, garlic and mustard oil sharpened with turmeric and chilli, and eaten with hot rice. It embodies two hallmarks of the cuisine: the heavy use of mustard, and the Maithil love of saag (greens), without which, it is said, no meal feels complete.
Because the greens are preserved by drying, biriya turns a seasonal crop into year-round food — a thrifty village dish that has become a marker of Maithil home cooking. It is everyday fare rather than festive: the kind of plate that tastes of a Mithila kitchen rather than a celebration.