Sprinkle fish with seasoning salt. In a bowl, mix butter, garlic, scallions, mushrooms, soy sauce, water, and ginger. Place fish in bag and place bag in shallow baking pan. Pour scallion mixture evenly over fish. Pull bag closely around fish and seal the opening with a string. Bake in preheated oven at 350 degrees F for 30-35 minutes.
By Robin from Washington, IA