Cook a full meal in a single dish -- fish and vegetables steamed to perfection in the microwave.
In a 9-by-13-inch microwave-safe dish, combine spinach, mushrooms, and scallions. Place salmon fillets on top, and sprinkle with salt and pepper.
In a small bowl, stir together mustard and orange juice. Spoon mixture over salmon. Microwave on high for 8 to 10 minutes or until salmon is cooked through and spinach has wilted. Serve salmon over vegetables.