Start by preparing your kale leaves. Rinse the leaves well and shake off any excess water. Pat the leaves dry with a clean cloth or kitchen towel and discard any tough stalks or stems.
Add the prepared kale to a large mixing bowl. Drizzle over the balsamic vinegar and olive oil. Sprinkle over the chili flakes and season with salt and pepper. Use your hands to thoroughly massage all the liquids and seasonings into the kale leaves.
Transfer the seasoned leaves to the basket of your air fryer. Ensure that they are in an even layer. Set the temperature to 375 degrees Fahrenheit and the timer to five minutes.
After five minutes the chips should be evenly cooked and crisp. These are best eaten immediately.