Preheat the oven to 425 F and line a 12 cup muffin pan with paper liners.
In a medium bowl, whisk together the flour, baking soda, baking powder, salt, pumpkin pie spice and cinnamon.
In a large bowl, whisk the pumpkin puree, granulated sugar, brown sugar, vegetable oil, milk and vanilla until smooth.
Add the dry ingredients to the wet and fold with a spatula just until no flour streaks remain. Do not overmix.
Divide the batter evenly among the liners, filling them almost to the top. Stir the topping sugar and cinnamon together and sprinkle over each muffin.
Bake at 425 F for 5 minutes, then lower the oven to 350 F without opening the door and bake 14 to 16 minutes more until tall and a toothpick comes out clean. Cool in the pan for 5 minutes, then transfer to a rack.
