I love the filling in the Kit Kat, though I could see how it could be a non-factor for others. I actually eat the chocolate off and then separate the wafer layers when eating a Kit Kat, but I'm weird, lol. That being said, I'm a HUGE, HUGE fan of Toba Garrett's chocolate buttercream. You can find the recipe on epicurious.com It has a few more steps than some might like, but it is so tasty. I sub more butter for the shortening in the recipe. I don't like powdered sugar based icings for the most part. I usually use Italian Meringue BC, unless it's a cream cheese icing, but this one is really good.