Add the oat flour, coconut flour, salt, baking soda, baking powder, and pumpkin pie spice to a bowl. Whisk to combine
In another bowl, whisk together the pumpkin, milk, vanilla, eggs, and maple syrup until combined
Add the dry ingredients to the wet, and use a rubber spatula to stir until just combined (do not over mix)
Fold in the chocolate chunks
Line a muffin tin with parchment paper muffin liners (these will allow the muffins not to stick) **see notes
Distribute the batter evenly into the muffin tins
Sprinkle the tops with additional chocolate chunks
Bake the muffins at 425 degrees for 14 - 17 minutes, until a toothpick inserted comes out clean