One of the reasons I desperately want to time travel is to blow the minds of people in the past with just the simplest of things today. Imagine going back hundreds of years and baking this gold 24 'carrot' cake. With a few drops of food coloring and a few edible gold leaf sheets, I'd be hailed as the greatest alchemist in the world.
The recipe for the 24 carrot cake (which actually does use 24 baby carrots) can be found at Instructables. The decorative gold bar is just a mix of white and yellow fondant with red, yellow and green food coloring and sheets of edible gold leaf sheets.