Mix marinade ingredients in a bowl. Add the fish and marinate for at least 30 minutes.
Heat up oil for velveting in the wok (flash frying the fish). When oil is hot, place the fish in the oil and stir fry for about 20 seconds. Drain in a colander
Empty the wok of all but 2 tbsp of the oil. Add garlic and stir fry for a few seconds until fragrant.
Add the doubanjiang and stir fry until fragrant. Add chili sauce stir fry for a couple seconds then add in the bean sprouts and napa cabbage. Stir fry for about 30 seconds
Add 2 cups of stock and stir fry to mix.
Add 1 tsp ground Sichuan peppercorns, red chilis, and soy sauce. Then add salt to taste
Bring to a boil. Reduce heat to medium low, cover, and simmer for 10 minutes
Grab a big bowl, strain vegetables from broth and place inside the bowl. Add fish into the broth and stir fry for about 30 seconds. Pour fish and broth over the vegetables.
Top with red chilis, dried chili, Sichaun peppercorn, garlic, green onion