Wash and clean the fish without cutting it.
Season with salt and leave it for half an hour.
Place the fish in the centre of an oven proof dish and dot it with butter.
Bake it in an oven for half an hour.
Remove from the oven, place thin rounds of tomato on top, sprinkle with tomato sauce and put back into the oven for another ten or fifteen minutes.
Before serving, arrange thin rounds of cucumber, salad leaves and grated carrot, all seasoned with salt and pepper, round the fish.