Preheat oven to 350°F (175°C). Grease a mini muffin tin or line with paper liners.
In a large bowl, whisk together the pumpkin puree, sugar, vegetable oil, and eggs until smooth.
In another bowl, combine the flour, baking powder, baking soda, cinnamon, nutmeg, and salt.
Gradually add the dry ingredients to the wet ingredients, mixing until just combined.
Spoon the batter into the prepared muffin tin, filling each cup about ¾ full.
Bake for 18-20 minutes, or until a toothpick inserted into the center comes out clean.
Let the muffins cool in the tin for a few minutes, then transfer to a wire rack to cool completely.