Mix cinnamon sugar:

In a small bowl, mix together the sugar and cinnamon. Put aside.

Prepare paper towels:

Prepare a plate lined with paper towels and set it aside. Also have a second plate or serving tray ready for the finished donut holes coated in cinnamon sugar.

Heat frying oil:

Pour frying oil into a Dutch oven and heat over medium heat. Use a candy thermometer to heat the oil to 350°F (175°C).

Cut biscuit dough:

Use a small round cookie cutter to cut each biscuit, then form the leftover dough into balls of similar size.

Fry donut holes:

When the oil is ready, fry the donut holes in batches of 5 or 6 for about 1 minute per side, until they turn golden brown.

Coat in cinnamon sugar:

Place the fried donut holes on the paper towel-lined plate for about a minute. While still warm, move them to the bowl with the cinnamon sugar and toss to coat evenly. Transfer them to a separate plate.

Turn off heat:

After all donut holes are fried, turn off the heat under the oil.