Cut one round cake in half. Cut the other cake so one half is slightly larger than the other. Lay the square cake on your cake board. Place the two evenly cut cake halves at each end of the square cake.
Mix up a batch of green frosting. Frost the cakes on the board.
Mix up a batch of blue frosting. Place the unevenly cut cake halves side-by-side on top of the green cake. Frost these two pieces blue.
Mix up a batch of brown frosting. Pipe horizontal tracks up and down the blue cakes and around the green cake.
Place the licorice whips on each side of the tracks. Use kitchen shears to cut whips to the lengths needed.
Use rainbow licorice twists to decorate around the sides of the green cake and the sides of the blue hills. Use kitchen shears to cut these to the right lengths too.
Use a dab of frosting to glue a gum ball to the top of each licorice twist. Gently press pretzel sticks to the sides of the blue hills to look like supports for the roller coaster.
Pipe green frosting on the tops of the candy bars to look like seats.
With a sharp knife, cut the legs off the bear crackers. Pipe a line of frosting on the bottom edges of two bears. Glue them in their frosting “seats” on a candy bar. Repeat with the other bears and candy bars.
Use frosting to glue the candy-coated gum pieces on the front and back of each car for lights. Then glue four candy necklace pieces to each car as wheels.
Place the cars in a line on the cake, setting the wheels in the frosting tracks.
Cake Boards: You’ll need something to put your cake creations on. Cut a piece of cardboard the same size or a little bigger than your cake. Lay the board on a piece of aluminum foil. Cut the foil larger than the board. Fold the foil over the back of the cardboard and tape flat.
This recipe is excerpted with permission from <a href="http://amzn.to/1lnVC9O">"Dessert Designer: Creations You Can Make and Eat!"</a> by Dana Meachen Rau and published by <a href="http://www.capstoneyoungreaders.com">Capstone Young Readers</a>.