If you have used Graccus mince meat fruitcake and didnt get the achievement it could be for 2 reasons.1: you didnt wear all 3 parts of the clothes2: durability was missing on some of the clothes.2nd reason happened to me. I equipped last years clothes and durability was 0/0. Ate the cake and nothing happened.According to forums on battle.net, you can open a ticket and ask for 1 more piece of cake. I did and it took only few hours for me to get an extra piece of cake.But hurry ... if you havent received it and eaten it by january 2nd, 6.am servertime you have to wait for next Winter Veil.
Great, thanks blizz on making this one ach a sucky one. making have to do this everyday to just complete it.