Ceaser's. I tried just about everything else. It's the only food my kids seem to like. Good thing about Cesar's is the variety. They even have a Porterhouse steak and Filet Mignon!! My kids like the turkey and beef. I too use the loaf. Nature's Balance has one and PetCo has their own brand (can't think of the name right now). Just chunk it up into little bitty pieces and they devour it. Course, when all else fails, there's always chicken. Mine go gaga over lemon-pepper chicken.
Good luck, Suz