{These are Uncle Mike's cookies, in case you missed 'em.}
But, hypothetically, your hubby wants to take the family out for lunch and pick up the piano you bought for $99 that is still sitting at Goodwill. And let's say, you get to Goodwill and the piano is too big to fit in the SUV, so you have to run to Home Depot and rent a truck. Hypothetically.
By the time you get back home and are ready to get piping (I kinda love that expression "get piping"), the icing you stashed in the fridge is a little less that stiff.
As a matter of fact, it looks like this....
What to do?
1st: First, stir in sifted powdered sugar. I always have a little powdered sugar shaker in my kitchen for dusting on pancakes, etc. Start there. Keep adding until it feels stiff again.
2nd: Try piping on a a plate or a paper towel. (I was using a #16 star tip here.) Does the pretty little "shell" pattern stay, or does it get runny?
3rd: If the icing still not stiff enough, pop in back in your mixer bowl, add some more powdered sugar and with the paddle attachment, beat it on medium until stiff peaks form again.
Voila!
