I have used the same buttercream recipe for all of my cakes and it has always set and crusted perfectly. Suddenly, for the my last two cakes, I wake up in the morning and what seems like oil has oozed from the buttercream to make a puddle on the cake board. Does anyone know what may be going on???

Are you refrigerating your cakes after crumbcoating?

Nope. No refrigeration. Should I? I've never refrigerated my cakes unless there is something perishable in or on them.

NO. I wouldn't . I just thought that maybe you did refrigerate and that's what was causing your problem. I honestly don't know. I've never had anything like that to happen.

Have you changed brands of shortening? Do you use butter?

I was having a very similar problem recently.
I'd purchased the store-brand butter on sale rather than Land O Lakes. Never again. Ruined 2 cakes - fortunately just practice ones - with runny, drippy icing. Switched back to the Land O Lakes and everything was back to normal.

Like mamawrobin said, see if you're using a different brand *anything* than usual. That's the only thing I can think of off the top of my head.

I've had this happen using the same brands of things. It isn't all the time but ever now and then. Was your icing softer than normal? Your house warmer than normal? Your cakes moister than normal?

I have had this problem a couple of times using IndyDebi's bc recipe. The icing crusted really well but a pool of liquid, probably grease, developed at the bottom border of the cake. Once it happened in August, which in Texas I can kind of understand, but the other time it happened in March when it is cooler. I don't think I have tried this recipe with hi ratio shortening yet, but I'm hoping that maybe this would solve the problem.

could it be the no trans fat crisco?