Pat the trout dry. Make several slashes on each side, spacing 3/4 inch apart and cutting almost to the bone. Rub the salt and pepper into trout inside and out. Press some of the ginger and green onions into slashes and inside fish. Place trout on heatproof plate. Sprinkle with soy sauce and top with remaining ginger and green onions. Bring the water to a boil in steamer. Place plate with fish on steamer rack. Cover and cook until the fish is just opaque, about 9 minutes per inch of thickness. Remove the fish from steamer. Sprinkle with oil and serve. Makes 2 servings