Marinate the fish (Ingredients group 1): Slice the fish fillet diagonally. Marinate with salt, white pepper, rice wine & corn starch.
Fry the spicy topping (Ingredients group 2): In a wok (or a deep frying pan), fry dried chilli and Sichuan pepper in oil over a low heat until fragrant (do not burn them). Chop coarsely when cooled. Set aside.
Cook the vegetable (Ingredients group 3): In the same wok, heat up oil over a medium heat, stir in celery. Cook for 1.5 minutes or so (30 seconds if using bean sprouts instead). Transfer to a serving bowl. Set aside.
Poach the fish (Ingredients group 4): Heat up oil in the wok, fry garlic, ginger and spring onion. Add Sichuan chilli bean paste and chilli powder. Pour in water (or chicken stock). Bring it to a boil then gently place the fish slices into the wok. When cooked, pour the fish and the soup onto the vegetable.
Garnish the dish (Ingredients group 5): Garnish with fried spicy topping and coriander. Heat up oil then pour over to sizzle the spices. Serve immediately with plain rice.