In a large bowl, beat butter with an electric mixer on medium to high seed for 30 seconds. Add the 1/2 cup sugar, baking powder, salt, cinnamon, baking soda, ginger, nutmeg, and cloves. Beat until combined, scraping sides of bowl occasionally. Beat in pumpkin, buttermilk, egg, egg yolk and vanilla until combined. Using a wooden spoon, stir in flour until well combined. Cover and chill 3 hours.
On a lightly floured surface, roll dough to a 1/2-inch thickness. Cut with floured 2-1/2-inch doughnut cutter, dipping cutter into flour between cuts. Reroll as necessary.
Fry doughnuts, 2 or 3 at a time, in deep, hot fat (365 degrees F) about 2-1/2 minutes or until golden, turning once. Using a slotted spoon, removed doughnuts from oil and drain on paper towels. Repeat with remaining doughnuts and doughnut holes. Coat warm doughnuts in Spiced Sugar. Serve warm or at room temperature. Makes about 12 doughnuts plus holes.
In a small bowl, stir together sugar, ground cinnamon, and freshly grated nutmeg or ground nutmeg.