Princess loves sweet potatoes & that is the only treat I can really keep around all of the time, as opposed to lettuce, etc. 
 
I've been microwaving them so they're soft enough to cut then slicing & dehydrating them in the oven. They stay moist & slightly chewy and hold up. Plus I can make a "bigger" one for a special treat & teeny tiny ones for training, etc. It's one of few vet approved treats for her.