Preheat oven to 325 degrees (F)
Line an 8 x 8 baking pan with parchment paper
In a bowl, combine dry ingredients except pumpkin pie spice (oats, oat flour, flour, baking soda, baking powder salt, and brown sugar)
In separate bowl combine pumpkin, vanilla, oil, and pumpkin pie spice
Combine the wet and dry ingredients, and stir, then add in milk and white chips, and stir well.
Press into lined pan
Bake 20-25 minutes until lightly browned
Remove from oven and cut into squares (9 total)
Melt some more white chocolate chips (optional) and pipe into the top!
Refrigerate for 1-2 hours and enjoy!