Wash fish and pat dry. In a shallow dish, place flour and season with salt and pepper to taste. Dredge with flour until lightly coated.

In a pan over medium heat, heat around 1 inch deep of oil. Add fish and cook, turning once or twice, until both sides are lightly browned. Remove from pan and drain on paper towels.

In another pan over medium heat, heat about 1 tablespoon oil. Add onions, garlic and ginger and cook until aromatic. Add fish sauce and continue to cook for an additional 1 to 2 minutes.

Add water and allow to a gentle boil. Add black beans and continue to cook for about 3 to 5 minutes or until liquid is reduced. Gently add fried fish and cook for about 2 to 4 minutes or until heated through and coated with sauce. Season with salt and pepper to taste. Serve.