Badger sometimes has trouble with losing food in his jowls. I'll give him a treat and then I'll see it hanging out in his lip folds or he'll shake his head and send food flying. Is that what you mean by Pan having a hard time eating the treats?
I mainly use cheese (mostly cheddar or string cheese for treats I'll hand to him, but I've put ricotta in a squeeze tube and used that) pork/beef, hotdogs, doggie meatballs cut up into smaller pieces, dried sardines/anchovies (although these can get crumbly) or liver.
Besides the ricotta, I'll also put the thicker meat baby/toddler foods, peanut butter or cream cheese in a squeeze tube, but he's not the best at eating out of the tube.
The fact that the treat doesn't always make it down his throat doesn't seem to demotivate him, so I haven't put too much effort into eliminating the treat-loss. Cheese does seem to be the worst for getting stuck, but freezing it helps a bit. Now I just keep treats in the freezer. Keeps the cheese from melting so quickly when we're working outside/it's in my pocket and the dogs seem to like it in this heat.