1 box cake mix
2 round cake pans
2 containers vanilla frosting
Food colouring (black and blue)
Black decorating gel
Icing piping bag
Batman action figure -- and maybe a Batmobile too!
Bake the cake in 2 round pans as directed on the box. Let cool.
Take one container of frosting and mix in the blue food color. Do the same for the other container with black food dye.
Frost both cake layers with blue frosting and stack them
Put the black frosting in a baking pipe, and pipe around the edges of the cake.
To create Gotham city on the side of the cake, take the black decorating gel and draw buildings.
Use the action figures as toppers.