How to Make It
In a small bowl, whisk the broth, soy sauce, vinegar, ketchup, sugar, wine, cornstarch and chile sauce. In a small saucepan, heat 1 tablespoon of the oil. Add the ginger and garlic and cook over high heat, stirring, just until fragrant, 1 minute. Whisk the sauce ingredients, then add them to the pan. Simmer until the sauce is thickened and glossy, 5 minutes. Keep warm over low heat.
In a large nonstick skillet, heat the remaining 2 tablespoons of oil until shimmering. Add the fish, skin side down, and press lightly with a spatula to sear the skin for 10 seconds for each fillet. Cook undisturbed over high heat until the fillets are browned and crispy at the edges and just barely opaque on top, about 5 minutes. Flip the fish and cook just until cooked through, about 1 minute longer. Transfer the fish skin side up to plates. Spoon the sauce on top, garnish with the scallions and serve with rice.
The sweet-and-sour sauce can be refrigerated overnight.
If using striped bass fillets, cook the fish for slightly longer.