Preheat oven to 325 degrees and line 24 cupcake tins with paper liners.
In a medium bowl, combine flour, baking powder, baking soda, cinnamon, and salt; set aside.
In a large bowl, whisk oil, pumpkin puree, eggs, and sugar until combined.
Add dry ingredients (and pecans if adding) to wet mixture and mix until just combined. Do not overmix.
Divide the batter evenly so each liner is 3/4 of the way full.
Bake 15-18 minutes or until a toothpick inserted in the center comes out clean.
Cool before frosting.