Fry the black pudding rounds in oil over medium heat until crisp on both sides and set aside.
Melt butter in the pan and fry the chopped onions for three minutes until soft.
Add the arborio rice and stir well to coat grains in butter and onion.
Add 750ml stock gradually by the ladleful, stirring constantly until the liquid is absorbed and rice is cooked.
Stir the curry powder into the cooked rice mixture.
Flake the smoked mackerel fillets and add them to the pan.
Gently fold in the chopped eggs, cooked black pudding, and fresh coriander.
Top the dish with additional flaked grilled mackerel fillets.
Serve in bowls garnished with freshly grated nutmeg.