Preheat the oven to 425°. In a small bowl, combine the cilantro with the garlic, scallions, ginger, lemon zest, salt and pepper. On a sturdy baking sheet, spread a sheet of heavy-duty aluminum foil large enough to wrap loosely around the fish. Sprinkle one-third of the cilantro mixture lengthwise down the center of the foil. Set the fish on the mixture and sprinkle another third on top. Drizzle the lemon juice over the fish and fold up the foil sides and ends, forming a loose but well-sealed packet. Bake the fish for 40 minutes, or until cooked through.