I was asked to do a car-themed cake for a boy who absolutely loves Lightning McQueen. I challenged myself to do it in 3-D. I am thrilled with the results! Took about 5 hours to decorate the whole thing. I used parchment paper cut-outs to design numbers and lightning that would fit.
The red is all fondant. The other colors are fondant/gum paste mix and the white is buttercream icing. I covered it in buttercream first. This is what it looked like then:
I had the 3 inch toy car as my model. The cake was three 9x9" cakes that were trimmed and stacked in various ways. The final cake is about 7"x14"x2"high. When I was done, I wanted the wheels to look like they were buried in sand (since they were flat on the bottom) so I sprinkled brown sugar all around the cake. I'm super impressed with how this one turned out!