Hi - welcome to CC!
So sorry to hear about your cookie troubles!
What icing recipe are you using? Are you getting actual spots or "blotchiness" in the icing? Do you have a picture you can post? Seeing it might help someone be able to tell you what's causing it.
White "spots" might be spots of sugar that didn't get mixed in enough, but "blotchiness" would be another reason...
I really believe in the white icing color to help with the blotchy icing problem. I also found that if I make sure they are good and dry before putting them away they do not blotch. I still freeze some of mine and when they thaw they still look great. Hope all this has helped.
I think it's drying them in the cold too. When I dry my glace cookies in my kitchen (I turn the heat off at night) I get blotchiness. When I bring the cookies upstairs where it is warm to dry I don't have the problem.
I had this problem when I started making cookies. I read where adding Wilton white icing color to the icing (5 drops per cup of icing)would prevent this. I did that and noticed a huge improvement. You could research this.
I really recommend you use Americolor instead of Wilton's white. Wilton's can change the texture of your icing and make it unappealling (learned the hard way, lol).
agree with what everyone said about heat. i dry mine in a warm room with no drafts.
diane
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