Preheat oven to 350 degrees Fahrenheit.
Line a cookie or baking sheet with parchment paper. If you do not have parchment paper, then oil the pan to prevent sticking.
Grate zucchini using the large holes of a box grater or food processor. Squeeze shredded zucchini using a kitchen towel or paper towels to remove excess moisture.
In a medium mixing bowl, add the shredded zucchini and peanut butter. Stir to combine.
Add the beaten egg to the zucchini mixture and stir to combine.
Next, add the oat flour and stir until the dough begins to form. These zucchini dog treats are soft, so the dough will be a bit sticky, similar to cookie dough.
Using a tablespoon scoop, scoop the dough into your hands and roll it into a ball. Then flatten into a 1/4 inch round and place on the prepared baking sheet.
Place in the preheated oven and bake for 12-15 minutes or until golden brown.
Transfer to a wire rack to cool thoroughly.