Preheat oven to 350°F.
Combine oil, eggs, pumpkin purée, and white sugar in a bowl.
1/4 cup oil, 2 eggs, 3/4 cups pumpkin purée, 1/2 cup white sugar
Add in flour, baking soda, and cinnamon and fold until a soft batter forms (I recommend switching to a spatula or wooden spoon to mix).
3/4 cups flour, 1/2 tsp baking soda, 1 + 1/2 tsps cinnamon
Grease mini donuts pan with oil or melted butter. Place batter into piping bag (easiest and less messiest method) and pipe to fill about 2/3's of the pan each.
Bake at 350°F for about 7-8 minutes. Insert a toothpick that comes out clean to know the donuts are ready for removal.
As they cool, whisk together white sugar and cinnamon. Coat the donuts in melted butter, and toss in the mixture.
1/4 cup white sugar, 1 + 1/2 tsps cinnamon, 4 tbsp butter, melted
Enjoy!