I have several of the KONG Classic Stuffable Dog Toys. I use some of Foxy's dry dog food and mix it with a little bit of leftover (usually) meat and a little water mixed together to stuff them with. I put them in the freezer and get one out every morning that I go to work and give her one. Freezing them makes it take longer for her to get all the goodies out. I started this when she was young and we were working a lot to keep her from being upset when we were leaving. Boy do I get a dirty look and told off if I almost forget to give her one. I guess that wouldn't work for a very big dog, but she is only about 15 lbs and not an aggressive chewer.