If you have ever visited Kolkata during the monsoon, you've probably indulged in the city's legendary chop, cutlet, and telebhaja or fried food culture. And if you have ever had any of Bengali cuisine's particularly fried classics like Kolkata-style fish fry, batter-fried fish, fish kobiraji, or mutton cutlet, it's likelier that you had it with a side of thinly sliced onion salad and a dollop of a pungent, fermented mustard sauce known as Kasundi.

A Condiment With A Fraught History Of Caste And Gender Politics

Once relatively unknown outside the borders of Bengal, Kasundi is a pungent, fermented mustard sauce used as a dressing, condiment, and seasoning in traditional Bengali cuisine. Although commercially made and sold in most supermarkets and grocery shops these days, historically kasundi was made at home for household consumption. Except, not everyone could make kasundi — they weren't allowed to.

According to Renuka Devi Chaudhurani, the doyenne of Bengali cuisine, Kasundi-making was a strictly caste-governed process. Originally, only Brahmins were allowed to make Kasundi, while married women were delegated the tasks of washing, drying, and pounding the mustard seeds into a fine paste. Even in households where other women were allowed to make the condiment, the Brahmin's role remained critical: they determined the auspicious timing, lit the fire to boil the water, and even placed the earthen pot on the stove. The ritual was as much about maintaining caste purity as it was about preservation and taste.

The Intricate Ritual Of Making Kasundi

The time-consuming process of making Kasundi began on the day of Akshaya Tritiya in late April or early May, after the mustard seeds were harvested and dried during the winter. The early summer months — not too cold to interfere with the fermentation process, nor too hot or humid to spoil the Kasundi — was considered ideal for Kasundi-making.

Traditionally, Kasundi-making was a highly ceremonial process, deeply embedded in seasonal, religious, caste and gender-based practices. Kasundi was made on Akshaya Tritiya, when all the black and yellow mustard seeds to be used for the year were washed in one go by married women who bathed in odd-numbered groups, faced east, wore wet sarees, and chanted for prosperity. The mustard was washed in rivers, or a running water stream, using a man's dhoti for straining — never a woman's saree.

After being sun-dried and sifted, the mustard was brought home with ghee lamps and ululations. It was then offered to the family deities along with fruits, betel leaves, and rice paddy. The seeds were then pounded for days with spices, green chillies, and sometimes raw mangoes, using water from the same river or waterbody, boiled in a new earthen pot. In her book 'Stree Achar' (Women's Rites), Chaudhurani mentions a dozen spices that were added to the mustard paste to make Kasundi, including green and black cardamom, cumin, coriander, nutmeg, mace, long pepper, chillies, black pepper and wild celery seeds, but this spice mix varied from family to family.

Only a woman with a living husband was allowed to place the paste in the pot, which was touched only after bathing and wearing fresh clothes. The mixture was then left to ferment for two days, developing its signature pungency and tang. It was first tasted by pregnant women in their third trimester as part of the shaadh ceremony, and then sealed and sunned for a few more days. Finally, on an auspicious weekday, a portion was placed in a sanctified pot, ritually sealed, and stored until Ashadh (June–July), when it was ceremoniously opened. On that day, the household abstained from fish, and Goddess Parvati was worshipped as Nistarini by high-caste Hindu women in some districts — marking the condiment's sacred place in the seasonal and spiritual life of Bengal.

Kasundi's Place In Contemporary Food Culture

Kasundi was sacred and cherished because of both how it was made and who made it. But this ritual exclusivity also meant that oppressed caste groups, particularly Dalits and Muslims, were historically excluded from making or even being served Kasundi in 'pure' upper-caste households. It wasn't just culinary practice; it was a tool of social separation.

And yet, like many traditions shaped by caste, the story of Kasundi is also one of adaptation and subversion. With time, as Bengal modernised and the rigidities of domestic caste practice began to loosen — especially in urban and diasporic spaces — the sauce found new hands, new methods, and new meanings. Muslim and Dalit households developed their own fermented relishes. In Bangladesh, where religious and caste lines followed a different trajectory post-Partition, Kasundi became more democratic — common in both urban and rural kitchens.

Today, Kasundi is undergoing another revival. In recent years, Kasundi-making has been commercialised by artisan chefs, used in fine dining restaurants, and fused with global dishes. It's no longer surprising to find Kasundi aioli, Kasundi hummus, even Kasundi Bloody Marys in restaurants and food pop-ups. But even as we relish Kasundi, we must question the caste-coded history that has shaped how it was preserved, who was allowed to make it, and who got credit for the craft.

This tension between preservation and reinvention, reverence and exclusion is common across many Indian food traditions. As fermentation is reclaimed globally as an art and science, Kasundi is an invitation to remember that not all heirlooms are benign, even as we celebrate them. Sometimes, they carry the taste of inequality.

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