Here is a really cool technique that you can use to copy images to a cake. This was my very first time using this technique. Although it did not come out perfect, I was very happy with the result. My husband really likes whipped cream frosting which was a little more difficult to work with than buttercream (the whipped frosting was only used to ice the cake, not for the transfer image).
3. Fill a bag with a colored icing (I used black) and tip 1. Outline the image completely.
Next, place the image still taped on the hard surface in the freezer for an hour or more. Ice your cake. When the hour is up. Take the image out, flip the parchment paper over on the cake and then quickly but carefully peel the paper back, leaving the image on the cake. If you need to alter the image in any way, you will need to wait about 20 minutes after transferring the image so that the buttercream is room temperature. Decorate the rest of the cake as you desire and you are done! I cannot wait to try this technique again and again and I assume that using a buttercream icing on the actual cake will produce a better result (you can see near the rear of the car how the image and whipped topping did not meet neatly).