Coat fish in the marinade, cover with aluminum foil, and refrigerate for 30 mins to an hour.
Heat oil in a pan, and fry the fish until it has seared and browned, don’t overcook. Remove and rest on a kitchen paper.
To make the khalta, heat the oil in a large pan. Add the onions and sauté until tender. Add the garlic and keep cooking – be careful not to burn. Add the tomato and follow with the tomato paste. Add all the spices as well as the stock cube, and then add the fish, chillies, fresh coriander and lumi.
In a small bowl, place a generous pinch of saffron with a little water and allow to infuse. Set aside.
To prepare the rice, bring a large pot of water to the boil. Salt the water generously, and add the oil. Then, add rice and cook on high heat for 10-15 mins. Drain and set aside.
In a larger pan, heat oil. Add a a layer of rice (around a quarter of the total quantity). Top with the fish and the khalta spice mix. Then add the rest of the rice, drizzle over the saffron water, cover and cook on low heat for around 2 hrs. Serve with freshly chopped coriander.