Now, now...they are from England, what do you expect?
In that case, boil them to death, then whip until they're the consistency of wallpaper paste. It will be like a taste of home for them.
Otherwise, I'd vote for a gratin. If you were serving to to me, I'd top with Raclette, but since they are from England, you might consider something milder like Fontina and Cheddar.