From Webkinz Insider Wiki
Tusslepuff is a stove recipe made with broccoli, fish sticks, and peach.
It was solved by Webkinz Insider member fumble99 on August 15, 2010.
webkinznewz.com reported that this recipe was solved on October 1st, 2009 by CAP with Pacey. However, WebkinzNewz never posted the ingredients for this recipe so it remained unsolved.
This recipe was solved one year, three months, and thirty days after its release date.
Tusslepuff was unsolved for more than one year, which makes it one of only nine secret recipes to have ever reached that milestone. The others are: Aminkle Grog, Boiled Wyvernacle, Epochiquox Glimmer, Gladdugrumble, Petallastar Pop, Spiny Sporcues, Spranklebeek, and Yummytummy Tumbler.
The Webkinz Newz has this to say about the recipe: "This interesting recipe is sure to invigorate your pet!"