not sure if there is a tutorial, but it's pretty simple. Trace a drawing of a tiara you like (there is a template in the gallery) and tape it on a can, peanut butter jar, etc., fitting the size you want it to be. Put parchment over the template. Pipe royal icing or candy melts over the template. Don't use a tip that is too small or you risk breakage.
Good luck!
Here you go:
Tutorial:
http://forum.cakecentral.com/cake-decorating-ftopict-97131-.html
Templates:
http://www.cakecentral.com/cake-decorating-photos_display_121_-129783.html
http://www.cakecentral.com/cake-decorating-photos_display_121_-87021.html
http://www.cakecentral.com/cake-decorating-photos_display_121_-84163.html
http://www.cakecentral.com/cake-decorating-photos_display_121_-40748.html
http://www.cakecentral.com/cake-decorating-photos_display_121_-40747.html
http://www.cakecentral.com/cake-decorating-photos_display_121_-24970.html
HTH
Here you go: http://forum.cakecentral.com/cake-decorating-ftopict-97131-.html
And this young lady was kind enough to make a template. I bet she would tell you how she did it if you pm her.
http://www.cakecentral.com/cake-photo-24970.html
HTH!
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