Preheat oven to 220oC.
Clean and scale the fish. Make 2 slashes in the thickest part of the fish flesh. Place a large piece of foil (big enough to encase fish) on a baking tray. Brush the foil with oil and place fish on top. Brush the flesh with remaining oil, season with salt flakes and cracked pepper.
In a small saucepan, combine ginger, chilli, soy sauce, coriander, garlic, lemongrass, lime zest and lime juice. Cook on low heat until the ginger softens (approx. 5 mins). Pour over the fish and seal the foil tightly so that no air can escape.
Bake for 30 - 40 minutes or until the fish is cooked through (when the flesh flakes away easily).
Place the fish on a large plate. Pour over the cooking juices and garnish with fresh lime slices.