Preheat oven 300 F.
Dissolve veggie cube or packet in the boiling water.Mix dry ingredients; mix wet ingredients separately, except egg. Pour wet ingredients into dry; mix lightly. Add a well in the center and add the egg. Mix.
Place dough on a lightly floured surface, sprinkle a little flour on top. Roll out to not more than 1/8". To avoid dough sticking to rolling pin, sprinkle a little flour on top of dough. The key is not to use too much flour. They will puff up otherwise.
Cut out shapes with a cookie cutter.
Place on ungreased cookie sheet. Bake 15 minutes., turn them over and bake another 10 minutes.
Cool on wire racks. Store in an airtight container.
Storing Dog Treats
In general you should store dog treats the same way you would homemade people cookies. That being said, there are two main variables that determine storage time - the amount and type of fat in the recipe and your local weather conditions. If your recipe uses fats such as butter, or meat bits or juices then it will be more prone to rancidity than a recipe that uses some vegetable oil or shortening. Your treats may mold or spoil much faster in humid or very hot climates.
Refrigeration and Freezing - Refrigeration will prolong the life of more fragile dog treats. Make sure to store in a tightly sealed container or zip lock bag. You can also freeze most treats in zip lock freezer bags. Allow to thaw completely before use.