Brush the steaks with a little oil and sprinkle with salt and pepper.

Spread the bread on 1 side only with the mustard. Dip the other side of the bread into the beaten egg, then into the grated cheese.

Heat the grill to high.

Melt the margarine in a large frying-pan, add the slices of bread, mustard side down, and fry over gentle heat for about 5 minutes until golden brown and crisp. Remove from the pan with a fish slice and drain well on absorbent paper. Cut each slice of bread diagonally in half and keep them hot.

Grill the steaks for 1 minute on each side for a rare steak, 2 - 3 minutes for medium to well-done steak.

When the steaks are grilled to your liking, place each between 2 triangles of fried bread with the cheese on the inside.

Serve the steaks on a warmed serving dish with the meat juices from the grill pan poured over.