The spicy fish （水煮鱼)

In china mainland, recent years, one kind of Si chuan (province) food called spicy fish （水煮鱼）is more popular. The meaning of its chinese name is fish boiled by cooking oil. The taste of the authentic spicy fish, like other sichuan food, is very very spicy. But more and more people like it, even some foreigners.
How to cook it? Actually, I don't know the details. For the restaurants which are selling the spicy fish, the ingredients are still a commercial secret. most diners only know: cut fish into very thin pieces, then pickle them with a special sauce, finally pour the boiling cooking oil on it with many many red peppers.
Yesterday, a friend who like to research cuisine invited my wife and me to have a dinner at his house. The major dish is the "spicy fish". In my memory, it was the third time that he cooked this dish for us. Each time he selected the different way to pickle the fish, because he is still discovering it. But yesterday, I think the third method is unsuccessful.