I'm pretty new at this, please tell me what happened!
I whipped up a big batch of SMBC this morning, and everything seemed fine. I put it in the fridge, and took it out this evening to work on my cake. Of course it was rock hard, and though I left it out for about an hour it still wasn't softening so I forced it into the stand mixer and tried to whip it, as I'd read that it should be rewhipped after being refrigerated.
It softened up then, but it got all grainy/runny, sort of curdled looking, and not at all spreadable.
Any ideas what I did wrong?
SMBC must come back to room temp on it's own, if it's cold and you force it into a mixer you will break the emulsion. It will come back together but the color, consistency, and the volume you had will be different.
Why did you refrigerate it? In the future that's unnecessary unless it's really warm (like, 80+ degrees) in your house, and that's only to prevent it from melting from the high butter content.
Good luck next time!