Cut the bread to shape of your choice. Use a knife or pastry cutter if you have one. These come in all sorts of shapes, for example, cars, trees, hearts, stars.
Switch the grill on and toast the bread on both sides.
Spread a little mustard on each slice, then top with the mature cheese, laying it as close as possible to the edges of the toast.
Sprinkle over the Worcestershire sauce to taste then pop under the grill. Cook for 2-3 minutes or until golden and bubbling. Be very careful when removing from grill.