Preheat the oven to 350°F.
Line two baking sheets with silicone baking mats.
In a large bowl, stir together flour, sugar, baking powder, pumpkin pie spice, and salt.
In a separate bowl, stir together the remaining ingredients (buttermilk, pumpkin puree, vanilla, egg, and butter).
Stir the wet ingredients into dry ingredients. Stir just until well mixed. Batter will be thick.
Scoop 1 tablespoon size amounts and shape them into balls using your hands. You’ll want to grease your hands for this step.
Place balls two inches apart on baking sheets. Bake one sheet at a time.
Bake for 14 to 15 minutes or until a toothpick inserted in the middle of the donut hole comes out clean.
Let cool for 5 minutes before adding the topping.