Fish deep fried with its skin on is succulent, with a crisp skin and moist interior. This would be one of my favourites ways to cook whole fish. The sweet and sour sauce can be adjusted by leaving out or adding ingredients according to your taste (in this recipe I use a little Chinese Chilli Sauce but it makes no difference if you leave it out). You may wish to use pineapple pieces in the sauce and leave out the shitake mushrooms, its up to you. I find the easiest way to deep fry the fish is in a large wok, filled a little less than 3/4 the way up with corn or sunflower oil.