I am about to put together my first cake from 'The Whimsical Bakehouse' book. The filling I'm using is called mousse, but it's really just whipped cream with orange curd mixed in. How soon in advance can I fill my cake before it starts to break down? I was hoping to do it today, 24 hours in advance of the party. Is that too soon?

Also, I've never used this type of filling, I'm assuming I won't need to dam it or anything like that, just smear it on and tidy up the sides of the cake? It's going to have a hot chocolate glaze poured over it.

Hmm.. that's a point, is the glaze going to destroy/melt the 'mousse' where it hits it?

It sounds to me that that filling has to stay in the frige. Yes make a dam.
Starts to break down? Properly whipped whipped cream doesn't break down. If it weeps it wasn't whipped enough. It's four hours cumulative out of the frige. It should last 24 hours chilled but I've never made it.

Your answer may be in there somewhere ^^^

lol... thank you, I have sifted through, I think I have my answer!

The reason I mentioned it breaking down is because the book mentions it will break down eventually, they just don't say how long it will take. Perhaps they're talking a week

OK, I've made some whipped chocolate ganache to use as a dam (I'm learning so many new techniques from this cake my head may very well explode), and will crumb it a little bit with that. Although I am dubiou as it seems to be mostly cream, the book says it should be used as a crumb underneath the choc glaze, so I'm having a little faith.

Right, off to clean up the huge mess I have made. Already run the dishwasher twice today. This one little cake requires such a lot of work, it better be ambrosia!

If you want to make your mousse more stable whip in three to four tablespoons instant vanilla pudding and fold in the orange. The pudding helps make the cream stable. I do this whenever I am working with whipped cream.