I trained Nilla on Zuke's mini naturals. They're tiny, round, and soft in shape and texture. They're
not chocked full of icky ingredients, but instead are all natural. She
loved them! I used the peanut butter flavor when I trained with her, but she also likes the wild rabbit. I have not tried all the flavors, but Nilla hasn't turned one away that she has tried (peanut butter, wild rabbit, chicken, venison). They're not wildly expensive, and with the precut, little pieces, I found a bag to last relatively long compared to other treats.
I am all for sticking with quality treats. Zuke's have never been recalled, and that means something when you go into these big box stores and see things on the shelves (or pulled from the shelves) that are on recall lists. It grinds my gears!
Best of luck! I've also heard a lot of people like to train with Merrick's Lamb Lung treats if you'd like variety!