Preheat the air fryer to 375℉.
Slice the hard ends off of the broccolini. About an inch or so should be perfect. Once cut you'll easily see the difference.
Now, toss the broccolini in oil, salt and pepper.
Put the oiled broccolini in the air fryer basket then cook for 7 minutes. Flip the vegetable around at the halfway mark.
Lastly, remove the cooked broccolini then serve. Squeeze the lemon over the broccolini if you decided to use it.