Gus' Peanut Butter Dog Biscuits

Preheat oven to 325 °. In a large mixing bowl, whisk together the milk, egg and peanut butter. Paula’s note: as a general rule, most homemade dog biscuits do well with 1 part liquid to 3 parts dry. You can customize the recipe by adding and subtracting ingredients your dog likes. Add in the flour and baking powder to make a very stiff dough, using your hands to work in the last of the flour if necessary. Flour a work surface and roll out dough to a 1/4-inch thickness. Cut into desired sizes depending on the size of your dog. Bake on a parchment-lined baking tray at 325 ° for approximately 20 minutes. Turn biscuits over and bake for an additional 15 minutes. Remove from oven and allow to cool completely before storing in an airtight container. Dog biscuits can also be stored in the freezer for up to 3 months.