Can it be left at room temp? If so, is four days too long?
Yes, it can be left out. Something with the ratio of shortening to liquid is what preserves it. I leave my cupcakes out for days when I make them and have never had a problem.
It is the amount of sugar in most American Buttercream Recipes, that preserves the milk. It will be fine left out at room type for 4 or more days.
oops.. thanks TexasSugar, that's what I meant.
Thank you both! I was hoping I didn't have to throw out all my b/c!
Nope, you are good to go.