Kasundi

What it is

Bengali fermented mustard sauce — a sharp, pungent, mustard-forward condiment. Traditionally a ritually prepared fermented relish; in modern usage often a spiced mustard-tomato sauce (especially in its Australian-adapted form).

How it's made

Traditional Bengali kasundi ferments crushed mustard seeds with salt, turmeric, and water, sometimes with raw mango or other additions, developing a sinus-clearing pungency. Modern and diaspora versions cook mustard with tomato, vinegar, chili, garlic, and spices into a relish-like sauce.

Flavor profile

Aggressively pungent and sharp from mustard (the nose-tingling, wasabi-like bite), salty and tangy, with chili heat; the cooked tomato versions are mellower and sweeter.

Culinary uses

Traditionally a dip for fried fish, vegetables (bhaja), and as a dressing for greens in Bengali cuisine; the modern relish is used like a spicy mustard-ketchup with grilled meats and snacks. Pairs with fried fish, pakora, grilled meats, eggs.

Regional variations

Bengali (West Bengal/Bangladesh) traditional fermented kasundi is the original, often with strict purity customs around its making. The "tomato kasundi" widely sold in Australia (via the Indian diaspora) is a spiced relish that's only loosely related.

Cultural & historical context

Kasundi held an almost sacred status in Bengali culinary tradition, historically prepared under ritual purity conditions in particular seasons, reflecting how seriously the fermented-mustard craft was taken. It's the Bengali answer to the region's love of pungent mustard, which also gives the cuisine its mustard-oil and shorshe (mustard-paste) cooking.

Reference notes

• Tags: fermented (traditional), pungent, mustard, spicy, vegan, refrigerate
• Related ingredients: mustard seed, mustard oil, raw mango, turmeric
• Related cuisines: Bengali (Indian/Bangladeshi)
• Suggested links: Achaar; Mustard (Dijon/Colman's) (compare); Bengali cuisine page