Preheat the oven to 400F/200C

Boil potatoes until tender. Drain well and mash. Season with salt and pepper and set aside to cool.

Spray a sheet of foil with non-stick spray and put the cod on the foil, season with salt and pepper and seal the foil tightly, making a packet. Put on a baking tray and cook for 20 minutes, or until just cooked through. Set aside to cool. When completely cool, carefully flake the fish into large pieces. Reserve the cooking juices.

Spoon the cold mashed potatoes into a bowl, mix in the spring onions, mayonnaise and mustard. Add 2 tablespoons of the fish cooking juice, then add the flaked cod and stir in the crabmeat. Add the parsley and hot pepper sauce and stir until combined. Season to taste.

Shape the mixture into 8 fishcakes, roughly 3 1/2-in/9cm diameter, this is easiest with damp hands. Place on a tray and refrigerate for at least 15 minutes.

Sprinkle the breadcrumbs on a plate and coat each fishcake. Return to the tray and refrigerate again for 30 minutes.

Heat a wide, heavy-based frying pan, add the butter and oil and fry the fishcakes over a high heat for 4 minutes on each side, or until golden-brown all over. When frying, it’s best not to overcrowd the pan, cook in two batches, if necessary.