1. Place the brussels sprouts in a large bowl and rinse well under cold water.

2. On a cutting board, slice the bottoms off the brussels sprouts, cutting off the base of the stem. Remove any damaged outside leaves as well.

3. Cut the brussels sprouts in half. If any pieces are noticeably larger than the rest, cut those pieces into quarters.

4. Put the prepared sprouts into a clean bowl and pat dry to remove extra water.

5. Add the oil, salt, pepper, garlic powder, and parmesan to the brussels sprouts and stir to coat evenly.

6. Preheat the air fryer to 400 degrees and set the timer for 12 minutes. When the temperature is ready, line the air fryer basket with a single layer of brussels sprouts. If needed, you can cook the sprouts in two batches to reduce crowding.

7. After the Brussels sprouts have finished cooking, remove from the air fryer and place onto a serving tray.

8. Drizzle with balsamic reduction and serve.