My son loves Disney's Cars, and what boy turning 3 wouldn't like a Lightning McQueen Cake? I am very crafty and a perfectionist, I've also made a Cookie Monster, Johnny Tractor and an alligator for my sons' birthdays. I love making cakes for my boys, but they do take a lot of time. Their birthdays are within a week of each other's so talk about pressure from the bar I've set!
I usually start gathering ideas and how to tips from www.coolest-birthday-cakes.com (I love your site). I draw pictures of the top and side views on paper (I traced the shape from my son's toy car) and enlarged it with the photo copier to get just the right size to fit my cake pan. I use a couple 9x13 sheet cakes and cut and piece together. In this cake I made a custard filling for in between the layers, but it drooped my icing on the back of the car where I iced the taillights (should have used stickers (if you've seen the movie a hundred times like me you'll get that:)
I have used chocolate and a vanilla pound cake recipes. I make the cakes ahead and freeze them until I'm ready to decorate, they stay very moist that way. I find the pound cake doesn't crumble when I carve the pieces. I followed the directions for the Wilton butter cream icing and I used the Cars icing pack. To personalize it for my son I put his age(3) in place of the 95, and I put his name (Cam) into the Rusteze spot. I still find black tough to make even starting with the chocolate icing, it looks very shiny to me because of the cocoa.
Once the cake is pieced and iced together then I use a toothpick to mark where I outline with black icing. I do all the outlining and then I used a star tip to fill in with the colored icing. The star tip helped me hide some imperfections. I use bamboo skewers to help move the icing if needed into just the right spot...voila a very cool birthday cake!