I remember one CCer said she made hers by molding fondant over the back of the pan she used to bake the rest of the "box" in.
styrofoam covered in fondant or gumpaste works well, use a wedge towards the back to prop it open
HTH 
Hi, Good morning! I hope someone can help me?!?
I don't know how to make a lid for a box (the kind that flowers/ruffles etc') pop out of?
Thanks!
I made a gift box cake last year and I made the lid using gumpaste. Here is how I did it.
I used the same pan that I baked the cake in. I simply inverted it and dusted the bottom with cornstarch. I then rolled out my gumpaste and draped it over the base of the cake pan and smoothed it all out. Once I had the gumpaste all in position I trimmed the edges of the box lid using a sharp knife. I then constructed the bow directly on the gumpaste base. I left the lid of the box on the pan to dry overnight.
I did this the evening prior to delivering the cake and it was not fully dried so I would suggest doing this a few days in advance. I slipped a cake board underneath of the base of the lid then I used chopsticks to support the lid so it appeared to be open.
I used a shorter chopstick in the back and then two longer ones in the front.
If you have any questions please feel free to ask.
Here is a link to the cake I made using this method.
http://www.cakecentral.com/mod.....&pid=43231
Here is a tutorial you may find helpful
http://forum.cakecentral.com/cake-decorating-ftopict-215781.html
Beth, thanks for that link.
Cake_Princess, thanks for posting your directions. For some reason I got an error message when I tried to open the link.
Sharon, thanks for asking this question/starting this post.
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