Preheat oven to 350°F. Spray donut pan with nonstick cooking spray. Set aside.
Mix together dry ingredients and set aside.
In a large bowl, add eggs, oil, sugars, and vanilla. Mix well.
Then add buttermilk to mixture and mix until incorporated.
Next, slowly add combined dry ingredients to wet. Mix well.
Lastly, mix in pureed pumpkin.
Transfer batter to a large ziploc bag (I place the ziploc bag in a tall cup to hold it while I scoop the batter in).
Cut the corner of the ziploc bag off (about 1/2" thick).
Carefully squeeze the batter into the greased donut pan – about halfway full for each (they will rise up a lot).
Bake for 8-10 minutes until the tops spring back to the touch. Once cooked, remove from pan.