1. Mix about 1.5kg cooking salt with 2 egg whites. The mixture will look like wet sand. 

2. Spread a thick layer of the salt mixture over the base of a shallow ovenproof dish or tin and put the fish on top. You don't need to remove the scales. 

3. Completely cover the fish with the remaining salt mixture, making sure there are no gaps. Don't worry if the tails are still exposed. Bake the fish at 200°C/gas 6 for 20 minutes, or until the core temperature reaches 57-60°C using a thermometer.

4. Remove the fish from the oven and crack the top the salt crust with the back of a large knife. Lift away the crust so that you can carefully lift out the fish. 

5. Put the fish on to a serving plate. Make a shallow cut through the skin along the backbone and behind the head of the fish. 

6. Pull the skin away from the top of the fish and lift off the two fillets. Turn the fish over and repeat on 

the other side.