In a mixing bowl, combine the cake mix, pumpkin puree, eggs and melted butter.
Mix until combined.
Add the mixture to a plastic pastry bag.
Twist the end of the bag and snip one corner with the kitchen scissors.
Gently squeeze the batter into the wells of the donut pan that has been sprayed with a non-stick spray.
Use a butter knife to spread the donut batter out smoothly.
Bake for 10 to 12 minutes or until a toothpick inserted into one of the donuts comes out clean.
Let the donuts cool slightly before removing them from the pan.
Stir the sugar and cinnamon together in a shallow bowl.
Working one at a time, brush the donuts with the melted butter, then dip them in the cinnamon sugar mixture to coat.
Serve warm or at room temperature.
Notes
FREEZING TIPS:
Place the donuts on a baking tray that's been lined with parchment paper and then place the tray in the freezer to flash freeze the donuts for about 30 minutes.
Remove the frozen donuts and place in a freezer safe container or plastic bag.
You can freeze the donuts for up to 2 months.
Thaw overnight in the refrigerator and warm up to your liking in the microwave.