Preheat oven to 350°F and prepare a muffin pan with liners.
In a large sized bowl, combine the flour, baking powder, baking soda, pumpkin pie spice and salt. Set aside.
In a medium mixing bowl, combine the melted butter and sugars. Whisk to combine.
Add the pumpkin puree, eggs and vanilla extract and whisk together until well combined.
Add the wet ingredients to the dry ingredients and mix just until combined. Do not over mix.
Fill the muffins liners about 3/4 full. Sprinkle with coarse sugar.
Bake for about 20 minutes until the centers spring back when touched.
Remove muffins from the oven and allow to cool.