Pre-heat oven to 160°C fan-forced. Line an oven tray with baking paper.
Place oats, sugar, flour, cocao and cinnamon in the bowl of a food processor. Pulse until oats are mostly processed, whilst still leaving some texture. Remove to a large mixing bowl.
In a separate bowl, whisk together the oil, egg and milk. Add to dry ingredients with choc chips and mix well.
Form into balls with your hands and place onto oven tray, pressing down to flatten slightly. Bake for approx. 12 mins until just firm. Allow to cool on oven tray, before removing to a cooling rack to cool completely. Store in an airtight container.