How to Make It
Put the mushrooms and black fungus in 2 separate bowl and soak in cold water for at least 20 minutes, or until softened. Remove the mushrooms, squeeze dry, and discard the stems. Dice, then set aside. Tear the black fungus into small pieces.
Meanwhile, use a sharp knife to make 5–6 slashes on each side of the fish. Pat the fish dry using paper towels and sprinkle with the salt. Marinate for 10 minutes. Lightly dredge both sides of the fish with cornstarch (cornflour).
Heat the 4 1/4 cups (34 fluid ounces/1 liter) oil in a wok or large skillet (frying pan) to 350°F/180°C, or until a cube of bread browns in 30 seconds. Add the fish and deep-fry for 4–5 minutes until golden brown and crispy. Use a slotted spoon to carefully remove the fish from the oil and drain on paper towels.
Add the garlic and ginger to the remaining oil in the wok, add pork, and stir-fry over medium heat for 1 minute until fragrant. Sprinkle in the wine, then stir in the pickled chiles, chili bean paste, mushrooms, fungus, soy sauce, and sugar. Add 1 1/2 cups (12 fluid ounces/ 350 milliliters) boiling water and bring to a boil. Add the fish, reduce to medium heat, cover, and simmer for about 5 minutes until cooked through. Flip over and cook for another 5 minutes until cooked through. Transfer the fish to a serving plate.
Bring the sauce in the wok to a boil. Simmer over medium heat, uncovered, for 2–3 minutes until the sauce has reduced. Finally, stir in the vinegar, white pepper, scallions (spring onions), and sesame oil. Pour the sauce over the fish, garnish with scallions and red chile, if using.