Does your child love trains? Then they'll love this sweet cake. The train cars are filled with candy!
For the train engine, cut one cake into a 6-inch piece, a 2-1/4-inch piece, and a 1-1/2-inch piece. Cut the 1-1/2-inch piece in half horizontally. For the two train cars, cut other pound cake in half crosswise. Tint 3/4 cup frosting red, 3/4 cup frosting yellow, and 1/2 cup frosting green. Cut thick pieces of cardboard to fit under engine and cars. For engine: Frost top and sides of 6-inch piece of cake red. Frost 2-1/4-inch piece of cake red on 2 sides and yellow on 3 sides. Place on large cake piece to make cab. Frost 1-1/2-inch piece red, and place lengthwise on engine. To make cars, frost top and sides of 2 remaining cake pieces -- 1 green and 1 yellow. Place frosted cake pieces on cardboard.
Using serrated knife, cut graham crackers in half lengthwise; trim to 4-1/2 inches. Place on cars to make bins to hold candy. Pipe crackers together with yellow frosting. Place toothpicks 1/4 inch apart just inside bin on yellow car to support candy. Using frosting, attach mints to Oreos. Place 4 Oreo wheels on each car. Place 4 wheels on engine at back. Using frosting, attach mini M&M's to mini Oreos; place on engine. Attach 2 fruit Gems and a Dot to make the smokestack, and a Gem and a Dot to make the headlight.
To decorate, place yellow mini M&M's around engine cab and red mini M&M's around engine top. Decorate the edges of the cars with mini M&M's as shown. Fill cars with candy; link together with Twizzlers. Remove toothpicks before serving.