Soak the fish briefly in vinegar to reduce any fishy smell, then descale and clean them. Marinate the fish with 1 tablespoon oyster sauce, 2 tablespoons golden sugar, 1 teaspoon seasoning powder, 2 tablespoons fish sauce, black pepper, minced garlic, and chili. Mix well and let the fish absorb the flavors for 15 minutes. Heat a pan and sauté garlic and onion until fragrant, then gently add each fish and fry until both sides are golden to help the fish stay firm during braising.

Occasionally turn the fish gently so both sides absorb the sauce. Add a little boiling water and adjust the seasoning to taste. Lower the heat and simmer until the fish changes color and the sauce thickens, then turn off the heat.