Preheat oven to 375 degrees. Grease a standard 12 cup muffin pan, or line with paper liners, set aside.
In a large bowl whisk together the flour, both sugars, baking soda, baking powder, salt, and pumpkin pie spice.
In a medium bowl, whisk together the eggs, pumpkin puree, vegetable oil, milk, and vanilla extract until smooth.
Pour the pumpkin mixture into the dry ingredients. Use a spatula to stir the mixtures together just until combined.
Use a cookie scoop or ⅓ cup dry measuring cup to spoon the muffin batter into the prepared pan. Fill each cup about ¾ of the way full.
Bake in preheated oven for 20-24 minutes, until a toothpick inserted in the center of one muffin comes out clean.
Remove the pan from the oven and allow the muffins to cool in the pan for 5 minutes. Remove the muffins to a wire rack and cool for an additional 10 minutes.
FOR THE TOPPING:
In one small bowl mix together the sugar and the cinnamon with a fork.
In a second small bowl, add the butter and melt in the microwave for about 30-45 seconds.
Dip the top of each muffin in the butter, then in the cinnamon sugar mixture.
NOTE ON STORING: These muffins are super moist, and they shouldn't be stored until completely cooled. Once cooled, they should be covered loosely, and are best eaten within 2 days. NOTE: You should be using 100% pumpkin puree for this recipe, do not substitute pumpkin pie filling.