Preheat oven to 350 degrees.

Combine all ingredients in a large mixing bowl.

Use a fork to mix ingredients until completely incorporated.

Using your hands, make a large ball out of the dog biscuit dough and let it rest in the bowl.

Meanwhile, sprinkle a bit of whole wheat flour on to a cutting board and rolling pin.

Transfer the dough to the cutting board and roll it out to 1/2" thick.

Use cookie cutters to individual cut dog biscuits.

Spray a cookie sheet with a light coating of cooking spray.

Place cut out biscuits on the tray. (Don't worry if you need to crowd them as they don't spread out while baking.)

Bake 30 minutes.

Remove from the oven and transfer biscuits to cooling racks.

After biscuits are cool, place them in a ziplock bag and refrigerate until serving.