- Preheat the oven to 350 °F / 180 °C.
- Scale and clean the fish, remove the gills, and cut off the fins and the tails.
- Lay the fish falt on a chopped board, and make 2 deep but short diagonal cuts in each side, leaving ½ inch between the 2 cuts.
- Prepare the seasoning by mixing the ginger, garlic, chiles, and salt into a paste, and stuff some in the cuts on both sides of each fish.
- Rub the rest of the seasoning paste all over the fish.
- Rub the butter over 4 pieces of aluminum foil.
- Place each piece of fish on a piece of foil, and sprinkle a bit of the garlic salt all over each piece.
- Loosely wrap up the foil to form parcels, and bake for 30 minutes.
- Wrap the crabmeat in foil, and warm in the oven for 10 minutes.
- Unwrap the baked fish and sprinkle the warm crabmeat over each piece.
- Serve each person a piece of fish and a crayfish tail, accompanied by chile sambal and dumplings.