Whisk the flour, baking powder, salt, baking soda and spices in a medium bowl. Beat the granulated sugar and butter on medium speed with an electric mixer. Beat in the egg and yolks, and then add in the vanilla. Stream in the buttermilk, and then beat in the pumpkin. Fold in the dry ingredients in two additions, blending gently after each addition. Chill for 3 hours.
On a lightly floured work surface, press out the dough to 1/2-inch thickness. Cut the dough using a small donut cutter and place on 2 well-floured baking sheets. (Scraps can be kneaded back together and re-rolled.)
Line 2 baking sheets with paper towels. Pour oil into a large, deep skillet to a depth of 1 1/2 inches. Attach a deep-fry thermometer and heat the oil to 365 degrees F to 370 degrees F. Fry the doughnuts until deep golden brown, about 140 seconds on each side. Using a slotted spoon, transfer to the paper towels to drain.
For the glaze: Whisk together the buttermilk, vinegar and powdered sugar. If it is too thick, add more buttermilk. If it is too thin, add more sugar.
Dip the warm donuts in the glaze and serve warm!!!!
Recipe courtesy of Zac Young