It's very humid here and sometimes leaving the royal icing on the cookie to dry makes the cookie soggy. Has anyone made a sugar plaque first and dried it then put it on the cookie? Would the "icing" be too thick and over power the cookie? Thank you for any help.

I always flow the royal icing onto the cookie. If you are having problems with it drying, you may consider putting it into a food dehydrator for a day or two to help.