Iron Man 1

The armoured faceplate is one of those outlines that needs no caption: angular jaw, slotted eyes, the helmet that has been turning up on lunchboxes and birthday cakes for two decades. It works as a biscuit because the silhouette is bold and symmetrical, which is exactly what a cutter wants. Superhero parties are the obvious use, but it does just as well for a comics-obsessed adult's birthday, a film night, or a tray of iced biscuits for a school fete. The face also gives an icer something to aim at — two eyes and a mouth slot are enough to make it read, so nobody needs to be handy with a piping bag. One cutter, kept in the drawer for whenever the next party comes round.