I have a client who wants to preserve a cake that I made for them. She said she's heard of a spray you can put on the cakes. Any of you ever heard of anything?

real cake or dummy cake?

I can't imagine how you can do this unless it's a fruit cake laced with whiskey or something even at that it won't last forever.

Really depends on what type of cake you are making.

Fondant will last a good while but I would imagine under the fondant would rot.

Dummy cakes is probably what she means. Whats the point in wasting food in this day and age?

The only spray I put on my dummy cakes is bug spray. Seriously.