I baked these twin princess Barbie cakes for my twin daughters' fourth birthdays. I used the Wilton wonder mold for the skirt and also baked a nine-inch layer cake to put beneath each one (to allow for using the full-sized princess Barbie dolls).
I made each cake layer a different flavors so we had a variety. Upon the advice of a friend, the eggs used in the cake mixes were at room temperature.
I baked all the cakes ahead of time, wrapped each individually in two layers of plastic wrap and froze them. On decorating day, I cut holes (the diameter of the dolls) in the center of the cakes while the cakes were still frozen (they stay together much better, and it's easier to cut the holes).
Then I set the bottom layer of each cake on a turntable (the same one I served them on) and crumb-frosted it. I then set each wonder mold layer on top and crumb-frosted. I wrapped each Barbie doll in plastic wrap up to her waist (and also wrapped Barbie's hair in plastic wrap to keep it clean) and placed one doll inside the top of each cake. To keep things fairly simple, I used the doll's existing bodice, sleeves and crown. They blended in quite well.
For the skirts I used Wilton Ready-to-Use White Rolled Fondant and tinted a portion of it pink. I used a Wilton fondant roller with a circular pattern to make the design on various parts of the skirts. I used cookie cutters in heart, leaf and oval shapes to make other decorative parts of the skirt from the fondant. Once all the fondant was applied, I "dusted" it with Wilton silver decorating dust using a small paintbrush. This, I will say, made the cake just "sparkle!" I decorated the seams and the waistline of each cake using frosting bags and various decorator tips. I used the star tip to make frosting stars at the skirt hems and stuck four candles on them for each cake.
Overall, it took me four hours to bake the cakes and four hours to decorate them. The cakes were completed two days prior to the big day, so I took an apple box and lid and stood each half on its side...slid a doll cake in each one and then taped plastic wrap over the open ends. The cakes were just fine and stayed very moist.
Our girls absolutely loved these cakes. They also loved being able to "twirl" them on the turntables. The local grocery superstore charges $44.99 for one Barbie cake like this (without the extra layer of height), so I felt pretty good about doing them myself. I think I enjoyed making them as much as our girls enjoyed having them as part of their princess birthday parties!