You could try using the Fondant. Use a bowl the size width of the cake, and shape the top to your desire. Just make sure to put wax paper under neith to ensure you are able to remove off of the bowl. Or try using the inside of the bowl. When dry, decorate!..
I just got asked to do one of these today! I did a search under google for "Wilton Traveling First Class Cake" and it gave all the details.
They say to use royal icing, I think I may try mine with fondant....
How are you going to do the wheels? they say to us pillers and cover them up with big cookies, but I am worried that it will be hard for her to transport? Unless there is some way to secure it to the cake board???
Good Luck, I hope this helps, may the force be with us!!
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