1 Heat the fish under a medium grill for 5 minutes on each side.
2 Remove the fish from the grill and open it by cutting along the back with a small sharp knife. Don't burn your fingers!
3 Remove the skeleton by gripping it at the tail end and gently easing it out of the fish.
4 Spread the fish with butter then sprinkle it with pepper. Put the two halves back together again and heat for a few more minutes.