Ikan Siakap Masak Masam Manis

My son is such a fussy eater. Never liked fish until one day when my mum took him to a Thai restaurant. He really liked the "sweet & sour" dish and kept talking about how sedap the fish was. Not to be outdone, I decided to show my son what his mum was capable of whipping up. If some people play the piano by ear, I cook based on taste - pegi restoren, makan, then go back and try to cook it my way.
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The ingredients:

1 medium-size siakap fish, 2 tablespoons of corn flour, 4 cloves of garlic - crushed, 1 inch of ginger - slice thinly memanjang, 1 onion - ringed, 1 green pepper - thickly-sliced, 1 tomato - cut into 6, cooking oil, 1/3 cup of maggi tomato ketchup, 1/3 cup of water, 2 tablespoons of sugar, 1/2 teaspoon of salt, white pepper to taste.

Garnish: green onions (daun bawang) & parsley leaves (daun sup) - chopped, pineapple cubes
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Preparation:

First of all, clean the fish (if you don't want to DIY, you can ask the fishmonger to do it. (removing the scales can be messy...). Next, rub the corn flour on both sides of the fish. The corn flour will make the skin tasty. Then, in a wok, deep-fry the fish till golden. Set the fried fish aside in a casserole. Garnish with green onions, parsley leaves and pineapple cubes.
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For best results, clean the wok before you use it again to cook the sweet & sour sauce. Also, do not use the same cooking oil that was used for frying the fish. Use fresh cooking oil.
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Sauce:
Heat 4 tablespoons of oil in the wok. Saute the garlic for a few seconds. Then, add the onion, green pepper, and ginger. Never put ginger first because it cooks fast, unlike garlic which takes some time. When the garlic turns golden, pour in the tomato ketchup (more ketchup, if you please). Stir for a few seconds. When the ketchup starts to sizzle, pour in the water (if you want more sauce, more water, then). Put in the tomato, sugar, salt and white pepper. Stir the sauce now and then. Simmer until you see the tomato skin starts to soften. Turn off the stove.
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Pour the sweet & sour sauce onto the fish. Serve hot with rice.