I am making a triple tier cake for my cousins 21st birthday, and I will not have much time to decorate it. Can I make the buttercream ahead of time and freeze it?

If so, are there any tricks to defrosting? Just on the counter top? Or in the fridge? How long should I allow for defrosting? And do I need to re-beat it?

TIA for any help!

Yes! You can. I do it all the time.

You can make it in advance and maybe whip it halfway. Cover it REALLY well so it doesnt get that freezer taste...then take it out the night before you want to use it so it gets back to room temp by morning. Then finish whipping it.

If you whip it all the way, you will probably have to whip it a bit again anyway once you defrost it. That is why I find it best to only whip it halfway if I plan on immediatly freezing the whole batch. Seems to turn out better once its defrosted.

Freezes great -- you'll definitely need to re-whip once it's at room temp.

I made a cake for a small wedding las vegas theme wedding reception last month. I am only a hobby baker and it takes me forever to decorate a cake. I was attending the wedding in Las Vegas then only had 3 day after we came home before the reception. I knew I would never pull it off if I didn't have everything ready before the trip.(Don't sleep much in Vegas!) I baked the cakes and made the buttercream then froze it all. Worked great. I got the frosting and cake out of the freezer in the morning before I left for work. Left it on the counter. When I got home I just gave the frosting a whirl in the mixer. The cake boards were already cut and covered and the fondant decorations had also been made ahead of time. Went together without any problems.

Thanks guys, I'm feeling more confident about this now!

I'm also glad to hear your vegas story, as that's pretty much the situation I'm in. I work fulltime, I have an 18month old baby, time is short! Party is on a Friday night, so it's not even like I'll have a weekend day to do it.