Pareidolia is when random images or sounds are perceived as significant. For example, seeing the image of the Virgin Mary in a water stain or hearing “Paul is dead” when you play a Beatles album backwards are both examples of the phenomenon.
Food, toast in particular, is often the bearer of images with an uncanny resemblance to famous figures throughout history. Click here for some examples and see if you can guess who’s face is toast (or a jelly bean).
See this piece at Skeptoid for more on the subject.