Get to know black mustard seed with fragrant Kashmiri-style fish kebabs

A strong, masculine spice, I slot black mustard seed into the category of astringent aromatics.

Astringent aromatics can be intimidating to use straight off the mark. What do I mean by astringent? Think onion, mustard oil, raw garlic; flavours that strip the nasal passages on scent or on consumption.

And yet the use of astringent spice can change the entire shape of a dish. When I think of black mustard seed, I think of a spice with the power to carve out a deeper palate.

Imagine your frying pan is a pit. Imagine black mustard seed is a shovel. Using this spice to dig a deeper hole in my pan means I then have more room to layer on top with its companion spices: ground cumin, chilli, curry leaf, yellow mustard seed, turmeric and (one of my favourite outsiders) sumac; Middle Eastern, yes, but no less delicious in Indian food for its foreign origins.

The seeds’ slightly bitter, hot and piquant quality match up to the natural salt and slight sweetness of the poached fish. Each fills the gaps of the other. The perfect partnership.

In the world of spice, using multiple aromatics ensures elegance and nuance. It may seem counter-intuitive, but when I broaden my palate of spice in a single dish, I find the resulting taste softer and a little more grown up – multiplicity creates gentle complexity. Which is precisely what’s required to turn out yummy machli kebabs.

We didn’t eat a lot of fish growing up; our Kashmiri heritage finds its roots more in mutton and chicken as far as proteins go. But these kebabs were occasionally on the menu. The fish to use here is one of mid-to-firm density flesh with some sweetness – think perch or red emperor or goldband snapper. A good fishmonger can guide you.

Fish is complex to spice. Though the flesh is delicate, its inherent profile of sea and salt and subtle seaweed aroma can consume spice if it is used too lightly; just as the essence of the fish will be lost if spice is used with too heavy a hand.

Black mustard seed works in this dish by nestling down into the flesh of the fish and spreading its aromatic fingers outward: the seeds’ slightly bitter, hot and piquant quality match up to the natural salt and slight sweetness of the poached fish. Each fills the gaps of the other. The perfect partnership.

With that initial marriage between spice and flesh secured, there is now a firm foundation upon which the companion aromatics can be layered. For me, this means the addition of yellow mustard seed, mustard oil, methi, finely diced raw onion and ground cumin.

This is strong, muscular spicing in an otherwise delicate dish that works for two reasons.

One, the spices are NOT heated before being mixed through the broken up, cooked fish and so their signature aromatic qualities are muted. And, two, the addition of a single raw egg to the mix provides both sweetness and viscose volume that subsumes some of that spice.

When cooking with spice, the intensity and texture and flavour profile of every tertiary ingredient added to the pan – be it oil or breadcrumb or egg or flour – needs to be taken into account.

Sarina Kamini is The Spice Mistress - spices tell her their secrets and she shares theirs with you. Don't miss her column, The Spice Mistress, on SBS Food. Keep in touch with her on Facebook @sarinakamini and Instagram @sarina_kamini.