I used a paw-shaped silicone mold because it is just too cute. But, you can use any type of silicone mold you have — the shape really doesn't matter. Or, if you prefer, you can mold these in a small paper Dixie cup instead. You will need to peel the cup off the treat once they are frozen. Another option for these 2 ingredient frozen dog treats is a simple ice cube tray. The dog treats pop right out when they're ready! Keep in mind that a smaller dog will appreciate a smaller treat. But, if you have a large dog, it's perfectly fine to give them larger-sized blueberry dog treats.