Preheat oven to 325 degrees F. Line baking sheet with parchment paper and set aside.
In a large bowl, whisk together the oats, oat flour, dried cranberries, pepitas, ground flaxseed, chia seeds, cinnamon, baking powder, and salt until well-combined.
In a medium bowl, mash the banana against the sides of the bowl using the backside of a fork until few lumps remain. Whisk in the coconut oil, maple syrup, and almond milk. Pour the wet ingredients into the dry and mix until just combined.
Measure dough out by the scant ¼ cupful and place on prepared baking sheet and gently flatten with the palm of your hand.
Bake for 15–18 minutes, or until cookies are lightly golden around the edges. Allow to cool completely before removing from the baking sheet.