We often think of granola bars as human treats, but they can make excellent dog treats as well when made correctly. These easy homemade Dog Treats are a great opportunity to hide ingredients like spinach that your dog might not be interested in. For best results, firmly press the mixture into the pan before baking to minimize rising. The ingredients below include frozen spinach, but fresh spinach can be wilted and substituted if desired. Making your own Dog Treats also allows you to know exactly what is going into the treat and the quality of the products used. This can be made organic and gluten free. You can even use this recipe as a base to add some fruit for an added nutrition boost.