In a large bowl, whisk together the dry ingredients -- flour, sugars, baking soda, baking powder, salt, cinnamon, nutmeg, ginger, allspice, and cloves until well mixed. Set this aside for now.
In a separate bowl, whisk together the wet ingredients--cooled butter, eggs, pumpkin, sour cream, and vanilla until very smooth.
Create a well in the bowl of the dry ingredients and pour the wet mixture over it. Use a spatula to fold everything together until just combined and no streaks of flour remain. Do not overmix! Some lumpiness is okay.
Cover and transfer the batter to rest in the fridge for at least one hour, or overnight for best results.
After resting the batter, preheat your oven to 425℉. Line every other cup of two cupcake pans and leave the others empty. This will give room for each muffin to grow. Use an ice cream scoop to fill the cups all the way to the top and then some. You will end up with 10-11 muffins depending on how high you fill them. Sprinkle the tops with some extra sugar if you desire.
Bake at 425℉ for 5 minutes, then lower then temperature to 350℉ and continue baking for 16-20 minutes, until the muffins are set and a toothpick comes out clean.
Let the muffins cool for 5 minutes in the pan before transferring them to a wire rack to cool completely. Enjoy!