Preheat the oven to 325 degrees. Line a baking sheet with parchment paper.
Place the oats in a blender and pulse until it becomes a flour like consistency.
Pour into a large bowl and add the fresh parsley, grated carrots, mashed banana, egg, and olive oil.
Mix until well combined and knead until moistened.
Turn dough onto a well floured surface. Use your hands to flatten the dough and shape into a circle 1/4 inch thick, using a bit of flour if needed.
Use a small dog bone cutter to cut out treats.
Place on a baking sheet lined with parchment an inch apart.
Place into the oven and bake for 35-40 minutes, or until golden brown and crisp.
Allow to cool on rack completely before storing them in an airtight container in the refrigerator for up to two weeks.