First I baked a 10" round (the base) box cake ( I think Duncan Hines Chocolate) and also baked a yellow box cake mix in a large mixing bowl for the "skirt"..iced both with buttercream, then rolled out fondant green & blue, green for skirt & blue for base.
Step 2: Stack cakes, insert barbie
Set the "skirt" on the base, if I did this again I would probably put some dowels in for support. Wrap the barbies legs in saran wrap & I also put her hair in a pony tail so it would not touch the cake. Gently push her legs down into the cake.
using tip # 233 tint some buttercream icing & make the "grass" on the skirt.
finish by rolling out some pink, yellow, blue fondant super thin & cut out flowers. Placing the flowers around the bottom of the skirt, then I cut out a "banner" in pink fondant & used the #3 tip with yellow buttercream to write her name/age.