Preheat oven to 375 degrees. Line two baking sheets with parchment paper and set aside.
In a large bowl, whisk together 1 cup peanut butter, pumpkin puree and eggs until smooth. Add two cups of the flour and stir to combine. Slowly add in the remaining 1 cup until a thick but malleable dough forms (you may have a bit remaining, that’s ok!).
Lightly dust work surface with additional whole wheat flour and roll out dough to ¼ inch thickness.
Using a dog bone shaped cutter (or whatever cutter you prefer), cut out biscuits and place ½ inch apart on prepared baking sheets. Bake in preheated oven for 15 – 20 minutes (less time for smaller treats or more time for crispier, crunchier treats). Remove from oven and allow to cool on wire rack.
While cookies cool, prepare the glaze, if using: melt remaining ½ cup peanut butter and beef tallow in the microwave until smooth. Drizzle over cooled cookies and let stand until glaze sets (that’s what the beef tallow is for).