I remember this being the highlight of our meal at Pizzafari a few years ago. Where else can we find it on our next trip? Do they have it at Flame Tree BBQ?
Are you just looking for it in AK? I have had it as a dessert at the Yak & Yeti CS.
Check the menus on http://www.allears.net for all of the locations that sell it all over WDW.
For instance, when I checked on there in AK for you, they also have it at Dino Diner, Drinkwallah, Harambe Fruit market, various ice cream carts, and many more. Some of these places even have frozen strawberry lemonade or frozen coke.