SAUCE: In a small bowl, whisk together all of the sauce ingredients.
Coat a 9 x 9-inch glass baking pan with non-stick cooking spray. Place fillets in pan side by side and pour sauce over them, tipping pan to distribute the sauce all around. Sprinkle green onions over fish. -
Cover pan with plastic wrap (leave one corner open to vent). Microwave on high for 5 minutes. (If you microwave doesn't have a revolving plate, turn pan a quarter turn halfway through cooking time.)
Remove plastic wrap and serve, putting a little of the sauce on each fillet.