http://bingweb.binghamton.edu/~tony/cake.jpg
Edited to add: This was on my friends list because of the
bakebakebake community, which linked to this post in good_eats. The person making that post says that her friend is the one who ordered and received the cake, so it's not like it's just some random photo that is floating around the internet and someone posted it. Also, as has been mentioned repeatedly in the comments, this is not hand-drawn icing, obviously! It is made on a printer and then laid on the cake. Yes, the cake seems to have blown out areas of total white: that's what happens when you use a flash. Also, the photo is kind of low-res which accounts for a lot of other things about it. I do photo editing as well and while I can see how there could be doubt in this case, I do not think that it is "obviously fake" because I can easily see how a real photo would come out looking exactly like this. 
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