I just made some IMBC frosting. It's not thick at all but soft. It tastes very good but I had made it to put in the orange dreamsicle cake I had made that is due for Saturday for my niece. I have a feeling I'm an idiot. I put it in the fridge to harden it some (hopefully) but my question is this...Will it hold up if I use it as a filling? Or should I just make something else? It's not super runny or anything, just soft and whipped looking. Won't it just soak into the cake if I try to use it as a filling since it is "whipped" looking? And if so, can I salvage it by adding something or should I make something else?

I just went to the fridge and it hasn't been in there long, but is defintely firmer. Sould I fill that layer and leave in the fridge 'till Saturday? The party is here so it will go on the cake and on the table!

oh let it firm up in the fridge but definitely before you rewhip it in your mixer....take it out and let it soften a bit otherwise it will simply crumble. To be honest I've even taken it straight from the refrigerator and for few extra quick seconds in the microwave then i whip it. Sometimes I even whip it by hand with a hand held wire wisk..it just depends. when you rewip..i start on slow and then immediately turn up to hi to really whip that puppy into shape. You should be fine. Italian meringue buttercream is very forgiving.

Did you whip the eggs to stiff peaks before adding the sugar? That may make a difference. And I mean very stiff peaks.