Ok so Last night I tried out SMBC for the first time, it turned out BEAUTIFUL! I was sooo excited. However, I ran out of time so I stuck it in the fridge and today pulled it out to become room temp. About an hour later I (too impatient to wait) threw it in the mixer where now it is mixing on low... soupy. Have I ruined it?!
Its not THAT big of a deal as I was just testing it out... but I would like to know for future reference.
to answer my own question... yes... yes it will after over half an hour of mixing!
It's best to let it come to room temp before whipping. All that butter will solidify when you put it in the fridge. Keep whipping the heck out of it and it will be fine. Someone else mentioned putting a warm towel around the bowl while it whips to warm the frosting a little.
Yes, you break down the emulsion when you move it cold. Just let it come up to room temp before mixing next time or pull out and melt 1/3 then mix it back in (same idea but faster in a pinch). You also don't need to refrigerate this icing overnight.
Put it over a double boiler and use an electric handmixer until it comes together. Should only take a couple of minutes.
Thanks for all the tips! Next time I hope to not have a situation like that!