I bought Lucy her first Kong about a week ago. It has made an incredible difference whenever she gets crated while I go to school. she doesn't put up a fight anymore.:D Anyways this is my concoction that i've came up with. I mix fat free cream cheese, peanut butter, and either sugar free applesauce or a jar of baby food (bannas, carrots, whatever i feel like picking up at the store). I also sometimes add some yogurt. I plug the small end with a liver treat and fill the rest with the mix above. I seal the large hole with either cream cheese or peanut butter. i fix the kong the night before and put it in the fridge. Also i put the kong in a plastic cup while i'm filling it up and leave it in the cup in the fridge till morning. It helps with it tipping over. Lucy seems pretty happy with this mix. Finishes it all up If anyone has any other ideas i would be glad to hear.