Preheat oven to 350°F (175°C) and line a muffin tin with cupcake liners.
In a large bowl, whisk pumpkin, oil, eggs, and vanilla until smooth.
In a separate bowl, combine flour, cocoa powder, sugars, baking soda, baking powder, salt, and spices.
Gradually add dry ingredients to the wet mixture. Stir until just combined—do not overmix.
Fold in optional chocolate chips or nuts.
Divide the batter evenly among the 12 cupcake liners, filling each about ⅔ full.
Bake for 18–22 minutes or until a toothpick inserted comes out clean.
Let cupcakes cool in the pan for 5 minutes, then transfer to a wire rack to cool completely before frosting.
Frost with cream cheese frosting, cinnamon buttercream, or ganache, and garnish with toppings of choice.