Ask the fish handler to fillet your fish, and reserve the head and bones. If the fish market doesn’t have this service, fillet the fish according to this video. (Optional) To serve the fish the authentic way, you can leave the fish skin on. It’s easier to cook the fish this way, because the skin will hold the flesh together, preventing it from falling apart. On the other hand, catfish skin is pretty fatty and might taste a bit greasy after cooking. If you don’t like the mouthfeel, remove and discard the skin.

To slice catfish, tilt the knife so it’s 45 degree against the cutting board. Slice fish in a sawing motion along the grain into 1/2 cm (1/4 inch) thick slices.

Combine fish, white pepper, salt, egg white, and cornstarch in a bowl. Gently mix the ingredients by hand until the fish is evenly coated with a thin layer of starch. Let marinate for 10 to 20 minutes.

Heat vegetable oil in a deep skillet (or a wok) over medium heat until warm. Add green onion, garlic, ginger, and chili pepper. When it starts to sizzle, turn to medium low heat. Cook for 1 to 2 minutes.

Add doubanjiang. Stir and cook until the herbs are evenly coated.

Add Sichuan pickles and jalapenos (if using). Cook and stir for 7 to 8 minutes. Add Shaoxing wine to deglaze the pan. Quickly stir a few times.

Add chicken stock. Cook over medium heat until boiling.

Add fish head and bones. Cook until boiling. Turn to medium low heat and let the broth boil for 15 to 20 minutes.

Use a pair of tongs to remove the fish head and bones. (Optional) The authentic Chinese dish will include these bone parts in the big serving bowl because they have fish meat on them. The meat on the head is the best part - very tender and moist. But if you don’t like this, you can discard the bones.

Transfer all the pickles to a big serving bowl.

Make sure there is at least 2 cm (2/3 inch) broth in the skillet, so the fish slices will be submerged later. Add more chicken stock if necessary, and return to a boil.

Add sugar, salt, and white pepper powder, mix well. Taste the broth and adjust seasoning as needed. The broth should be slightly salty.

Turn to medium heat. Add fish slices in small batches. Use a spatula to gently transfer the fish to the skillet, and use a pair of tongs to quickly separate the slices without tearing the fish apart. Cook until fish is just cooked through. Transfer the fish and soup to the serving bowl on top of the pickles.

Heat oil in another small skillet until warm. Add Sichuan peppercorns and doubanjiang. Cook and stir until the oil turns red and the peppercorns turn dark.

Use a spatula (or colander) to remove and discard the solid ingredients.

Pour the oil onto the fish while hot.

Garnish the fish with green onion and serve warm.