Award-Winning Fish Pie

Peel and chop the potatoes into even-sized chunks. Place them in a large pot with cold water and bring to the boil. Cook for 15-20 minutes, or until tender. Drain well using a colander.

Return the drained potatoes to the pot. Add butter, double cream, salt, and pepper. Mash the potatoes using a potato ricer for a smooth consistency, or a masher. Stir to combine and set aside.

Pour the milk into a saucepan and bring to a gentle simmer over medium heat. Add the salmon and cod fillets, and poach for about 3 minutes. If using raw prawns, add them for the last minute of poaching. Remove the fish and prawns from the milk, reserving the milk. Flake the fish into large pieces, removing any skin or bones. Set aside.

In the same saucepan, melt 2 tbsp of butter over medium heat. Whisk in 2 tbsp of plain flour and cook for 1 minute, stirring constantly, to form a roux.

Gradually whisk the reserved milk into the roux, a little at a time, to create a smooth sauce. Continue to stir gently (do not whisk vigorously to avoid frothiness) until the sauce has thickened. Stir in the grated cheddar cheese until melted and the sauce is creamy. Remove from heat.

Place the flaked fish and prawns into an ovenproof dish. Pour the creamy cheese sauce over the fish mixture, ensuring it is evenly distributed.

Spoon the mashed potato mixture over the fish and sauce, spreading it evenly to cover the entire surface. Use a fork to create a ruffled texture on top of the mash, which will help it crisp up in the oven.

Place the dish in a preheated oven at 200°C (400°F) for 15-20 minutes, or until the topping is golden brown and the filling is bubbling.