Combine all of the ingredients in your mixer's mixing bowl. Using the dough hook attachment, mix until everything is combined.
Turn the dough out onto a lightly floured surface.
With a rolling pin, roll the dough to 1/4 - 1/3 inch thick.
Now to cut the dough into treats. You can use cute cookie cutters if you like. I take the quick route and cut the dough into rectangles with a pizza cutter. How big or small you cut them depends upon your dog. Big treats for big dogs, little treats for little dogs.
Place the treats on two baking sheets that are lined with silicone baking mats or parchment paper. The treats can be close to one another, but shouldn't be touching.
Take a fork and poke several holes in each treat. Poke the fork all the way through to the baking sheet.
Bake the treats for 50 minutes, then turn off the oven and don't open the oven door. Leave the treats in the warm oven for at least 2 hours. This allows the treats to completely dry and harden.
Store the treats in an airtight container.
Your pups will enjoy these!
Notes
I have also made a modified version of this using all-purpose flour, omitting the wheat germ and using rolled oats instead. The treats still turned out great, and of course the dogs all loved them.