Preheat the oven to 350 degrees Fahrenheit.
In a mixing bowl, combine the oats, flour, baking powder, salt, sugar, and pumpkin pie spice.
In a separate bowl, beat together the pumpkin, milk, melted butter, and vanilla.
Add the wet ingredients to the dry ingredients and stir to combine. Mix in the chocolate chips.
Pour the batter into a greased 9x9 pan (or similar size baking pan) and bake for 20-25 minutes, until an inserted toothpick comes out clean.