To make it challenging, you have to pick one and only one. Treat it as if you are personally bestowing the Best Book of the Year award.
I rated a number of books 5 stars this year, some because they were great books, some because I just enjoyed them so much. Picking one as my personal Best Book of the Year is tough, but after considering the candidates, I must give the nod to:
The Golem and the Jinni, by Helene Wecker.
Both excellently entertaining and excellently written, it had no flaws or weaknesses needing to be overlooked, and thus is one of the few books I can recommend without qualification.
(Note: Coincidentally, my pick was also published in 2013, but this is for posting the best book you read in 2013, regardless of when it was published.)
Previous Saturday Book Discussions.