I made this special Homemade 4th Birthday Racetrack Cake for my son's 4th birthday to go with his "Cars" themed party. I used a 12x18 pan and three boxes of cake mix to make the cake. While it was cooling, I cut out a large number 4 out of posterboard, measured to the exact size of the cake pan. I placed the cut-out on the cake and frosted around it with vanilla icing dyed green. Then I frosted the racetrack with chocolate icing dyed black (using Wilton black dye).
To make the green icing become "grass", I added coconut flakes dyed green on top of all the green frosting. Then I dipped my finger in water and smoothed out the black racetrack frosting. I used a tube of white Wilton decorating icing to go around the racetrack and make the white lines in the middle. Lastly, I printed out two small banners that read "Happy 4th Birthday" and "Caleb!", with pictures of him as a baby and now. (This was a last minute change to my cake plan once I realized how difficult it was to write icing words on top of coconut grass. Whoops!) I taped two candles to each banner, for a total of FOUR candles for my son to blow out. He placed four cars on the track, and we were ready to race into a great party!
This "Cars" cake was part of "Sarge's Surplus of Sweets" at the party. Chocolate Dipsticks (pretzels sticks rolled halfway in melted milk chocolate), Cars Cookies, and Stoplight Rice Krispies also completed Sarge's table of sweets. You can also see a sign for "Fillmore's Organic Fuels" at the upper left. Those were Motor Oil (grape juice), Gas (Root Beer), and Anti-Freeze (lemonade dyed green.) Along with the foods we had in Flo's V8 Cafe, this Racetrack Cake was the perfect ending to our birthday celebration in Radiator Springs!