Preheat oven to 350 degrees F. Line a 9x9 pan with parchment paper.
In a medium bowl, make the flax egg by combining the ground flaxseed with water. Let it sit for 5 minutes to thicken.
In a large bowl, combine the oat flour, rolled oats, baking powder, pumpkin pie spice, cinnamon, salt, and chia seeds. Stir until well combined.
In the medium bowl with the flax egg, add the pumpkin puree, mashed banana, almond milk, maple syrup, vanilla, and peanut butter.
Add the wet to the dry. Stir with a spatula until just combined. Fold in nuts/mix-ins.
Pour batter into your lined pan. Bake for 30-35 min or until edges are golden and middle is set. Let it cool in the pan for 15 minutes, then carefully lift it out with the parchment paper and set on a cooling rack to cool completely.
Once cooled, melt the chocolate chips in the microwave in 30 second intervals until smooth. Stir after every 30 seconds and make sure you don’t burn it. Mine took a little under 60 seconds total.
Drizzle the chocolate over the pumpkin oatmeal bars. Slice and enjoy!
Store leftovers in an airtight container in the fridge for up to 1 week or room temperature for 2 days.