So this might seem a silly question, but anyway, here goes. We usually make our buttercream using only Crisco, because in our understanding if you make with butter you need to refrigerate it. Is this the case. Or would it be fine to leave it out for a couple days, including decorating and then a day or two on the counter after it has been cut?
I also find that the 100% Crisco is not very smooth and it is harder to get all the wrinkles out when we put it on the cake, but this might just be our lack of experience.
I use the Wilton recipe with half butter and half Crisco. I leave my frosted cake out all the time. I never refrigerate it when I'm done. My family has eaten on a cake for probably almost a week, and it's been fine!
Not all icings are alike A shortening based b'cream can contain real butter and still not need refrigeration . The sugar in it preserves the recipe. I wouldn't leave it out if it was mid summer and 80-90 inside you house but now should be just fine. And even then, I'd be more concerned about the cake more than the icing.
Jeaucl, here's a thread with cake and frosting recipes that has smoothing help and so much more:
Butter does not have to be refrigerated. In fact, it is perfectly safe to have a stick of butter out on the counter (in a butter dish) all the time. As long as it is 75 deg or cooler in your house, it won't go rancid before you eat all of it. We have butter out on our counter (in the butter dish) year round and I live in Atlanta, GA!
That being said, a cake iced with an all butter frosting will be just fine sitting out on the counter. Just make sure your room is cool. I find that cakes do best when the air temp is 65 deg or cooler. Remember: the warmer it is in the house, the softer the butter is going to get!
Even a cake iced with cream cheese frosting will be fine sitting out for about a day or two (the cream cheese will go sour long before the butter goes rancid).
*All temps quoted are Fahrenheit.*