Spray the air fryer basket with olive oil cooking spray or line it with foil and spray.
Place the butternut squash in the basket.
Sprinkle with cinnamon and coat with olive oil spray.
Cook at 390 degrees for 20 minutes. It's best to check on it after 10 minutes, stir, coat and continue cooking. At this point, you can also add more cinnamon if you prefer.
Serve.
Video
Notes
Remember all air fryers heat differently, I suggest checking on this at 10 minutes, then continue cooking.