1 Heat the oven to 200°C (180° fan) 400°F gas 6. Line a bkaing tray with non-stick baking paper.
2 Wash the trout inside and out and place in a dish. Dry the skin with absorbent kitchen paper.
3 Cut off the tips of the tail and the fins.
4 Season the body cavity with salt and pepper and place the lemon and orange slices, garlic and parsley inside the fish.
5 Brush the outside with olive oil.
6 For the crust: whisk the egg whites until stiff.
7 Add the coarse salt and mix well.
8 Spread 1/3 of the salt mixture on the baking tray. Place the fish on top and spoon on the remaining salt mixture, being careful to avoid creating cracks or holes. Press onto the fish. The fish must be completely covered and sealed. Sprinkle with a little cold water - this helps to form a crust.
9 Cook in the oven for 30-40 minutes.
10 Before serving, carefully remove the salt crust and skin.