Hummmmm - depends on what you want.

If you are looking for training treats I like the Bil-Jac liver treats. You can break them down into smaller sizes and get quite a few commands on one treat. Hot dogs and little pieces of cheese also work really well. Freeze dried liver treats also work well - but they are pretty big for a yorkie.

If you are looking for a treat to clean their teeth and breath I recommend greenies - they are a bit expensive, but do a great job. I also like the Innova dog biscuits - they smell good enough to eat yourself. My dogs like them a lot and they are also made with human grade ingredients.