Mackerel with rhubarb relish

Method

1. For the rhubarb relish: squeeze the orange juice into a pan and add the sugar, orange zest and water. Stir the coriander seeds, caraway seeds and kalonji or black mustard seeds into the mixture and cook over a medium heat for 5-6 minutes, or until the sugar has dissolved.

2. Reduce the heat and simmer for 10-12 minutes, or until the liquid in the pan has reduced to a thick and sticky consistency. Add the rhubarb pieces to the pan along with a pinch of salt, then cover with a lid and cook for a further 1-2 minutes, or until the rhubarb is tender.

3. Remove from the heat, then pass the mixture through a sieve lined with fine muslin, reserving the liquid. Transfer the solid material to a serving dish, then pour the liquid back into the pan and boil for 4-6 minutes, or until the liquid is thick and syrupy.

4. Pour the syrup back over the rhubarb and stir, then leave to cool.

5. For the mackerel: brush the mackerel lightly with oil on both sides, then season with salt and pepper on the non-skin side. Heat a griddle pan until smoking, then fry skin-side down for 1-2 minutes, then flip over and cook for a further 1-2 minutes, or until cooked through.

6. To serve, place the mackerel on a serving plate and spoon some of the relish next to it. Garnish with kalonji or black mustard seeds, then serve.