Hello, Im new to this site and Im sorry if this question has been asked before.. I made a batch of Italian buttercream a few days ago.. used a small amount and stored the rest in the fridge. I now want to give it a whip and use it.. but it seems to have separated.. and producing liquid...when it was it was first made it turned out great.. beautiful texture... now not so beautiful. lol 

I used the cakeboss recipe from his cookbook. 

Did you let it come to room temperature before rewhipping it?

AGently warm the bowl with a blow dryer or space heater while mixing with beater blade. Watch it carefully. As soon as starts to come together turn off the heat so it doesn't melt. Continue to mix until smooth and creamy. I have saved some hopeless separations his way.

Thanks for your reply! Yeah it seemed to be close enough to room temperature.. I had it sitting out for a about 4 hours.. Maybe its still too cool? Ive never stored italian buttercream before, made it many times but usually use it all at the time.. 

Oh thankyou.. I will give it a try. 

The blow dryer is a great idea!  Or you could also put a small amount in a separate bowl and microwave it for mere seconds, and then add that to your mixing bowl.  I've done that before with cool SMBC, and it's helped bring the temp up enough that it rewhips nicely.

I've had luck doing a couple different things.   Let it come to room temp before you start to re-whip, or you can also microwave it for a few seconds before whipping.  You could also torch your mixing bowl while its whipping.  If its still broken and separated, I've had luck adding a small spoonful (tbsp or so) of sweetex.  This is my last ditch resort obviously, but it seems to work like magic.  I'll try anything before I toss product out!!  

The blow dryer worked!!!!  Thank you so much!! Im glad I come on here and asked.. Ive been on this site to browse the beautiful cake photos but never really went any further... I need to ask more often   

I have had it break down several times when I thought it was room temp too.  If not sure, or if I forget to take it out of the freezer or refrigerator ahead of time, I cut the buttercream into chunks and pile into a bowl.  Microwave it very carefully on defrost setting just 5 seconds at a time, redistributing the buttercream after each 5 seconds until it is soft like soft butter and even a teensy bit shiny/melty on a few edges.  If too soft, pack ice packs or frozen gel packs around the bowl while remixing.  (The things we do for our cakes!)