What are the best training treats for a puppy?

This is a question for your puppy. :) they are all individuals. How is the puppy's drive for food and treats?

I like to try a lot of different things to see what is of high value for that particular dog. You want a soft easily swallowed treat, not a biscuit or something large that takes time to chew.

Some favorites with my own dogs are meat rolls diced up into appropriate size pieces, freeze-dried liver, and other commercially available treats. Some dogs with high food drive will work for kibble (I don't feed kibble so I tend not to use this.)

String cheese sliced up into appropriate size pieces, cooked liver or steak. You don't want something that crumbles.
I'll link some of my dog's favorites below.

When I use the meat rolls I dice up a whole roll and divide it into baggies and freeze most of it so I have treats ready when I need them.