Preheat your oven to 350°F (175°C).
Line a muffin tin with paper liners or grease it lightly.
In a large bowl, combine the pumpkin puree, granulated sugar, brown sugar, and vegetable oil.
Add the eggs one at a time, mixing well after each addition.
In another bowl, whisk together the flour, baking soda, baking powder, spices, and salt.
Gradually add the dry mixture to the wet ingredients, stirring just until combined.
If desired, fold in nuts or chocolate chips gently.
Spoon the batter into the prepared muffin tin, filling each cup about 2/3 full.
Bake in the preheated oven for 18-22 minutes or until a toothpick inserted into the center comes out clean.
Remove from the oven and let cool in the tin for about 5 minutes before transferring to a wire rack.
Enjoy your freshly baked pumpkin muffins warm or at room temperature!