Break the graham cracker in half so that it makes two even squares, and sandwich the chocolate between them.
Turn one burner on your stovetop up to high heat. If you have an electric stove, allow the coil to heat up fully.
Place the marshmallow on a skewer, chopstick, or long fork. Hold the marshmallow a few inches above the burner and toast it just as you would over an open fire, until it is molten and golden brown.
Place the skewered marshmallow between the two graham crackers, on top of the chocolate and, squeezing the crackers together, pull out the skewer.
Allow the marshmallow to sit for a minute, to fully melt the chocolate before enjoying. Please supervise children if using this method!