You can store icing at room temperature for 2 days, then place in fridge wrapping well without air getting to it, in a container with plastic wrap over the top, then a lid, or in a zipper-plastic bag with air pressed out. Bring to room temperature, stir well then use.

That is very helpful! I’m so glad to know this, now I won’t be afraid to use this icing! I would have left them on cooling racks so I also appreciate your tip on putting them on a baking sheet. Thank you!

No the cookies don’t dry out. The icing actually keeps the moisture in the cookies. Before icing if you think the butter will rise up and interfere with the icing, allow cookies to set up for a day. Then ice them and then allow the icing to set for 24 hours before packaging. No the cookie won’t go stale. I worried about that in the beginning. Place all the cookies on baking sheets so the bottoms don’t get air flow under them. I don’t leave the cookies on cooling racks. That would allow air to surround the cookie and then I’m sure you’d get a dryer result. Hope that’s helpful. Let me know if you have any other questions.