Heat oil in a Dutch oven or deep fryer over medium heat until it reaches 350°F (175°C).

Line a baking sheet with paper towels and place a cooling rack on top.

In a medium bowl, whisk together buttermilk, pumpkin puree, vanilla, and egg until smooth. Mix in melted butter.

Add flour, baking powder, pumpkin pie spice, brown sugar, and salt. Whisk just until combined.

Once the oil reaches temperature, use a small cookie scoop (#50) dipped in oil to drop dough into the fryer, cooking in batches of 5–6.

Fry for 4–5 minutes until golden brown, turning occasionally for even cooking.

Remove with a slotted spoon and place on the cooling rack. Repeat with remaining batter.

Mix powdered sugar and pumpkin pie spice for the topping. Once donut holes are slightly cooled, roll or dust them in the sugar mixture.