Spread the breadcrumbs on a sheet of foil and grill until golden and crunchy, then leave to cool.

Season the cod steaks generously with salt and pepper on each side. Dot the butter or margarine over one side of the fish. Turn the grill on to medium heat. Place the cod steaks buttered side up on a sheet of foil and grill for 6 - 8 minutes.

Turn them over, mix togetherthe breadcrumbs, cheese, mustard and seasoning to taste, sprinkle over the fish and grill for a further 6 - 8 minutes.

Place the cod steaks in a hot serving dish, garnish with lemon twists and serve at once with jacket potatoes and a green vegetable.