Make a square “pan” out of aluminum foil with a lip all the way around to keep the juices from getting all over your air fryer and spray it lightly with cooking spray. It should be just smaller than your air fryer basket.
Preheat your air fryer to 400 degrees Fahrenheit.
Whisk together the melted butter, lemon pepper and brown sugar in a small bowl, with a fork or wire whisk.
Place the 3 filets on it, skin side down, with about ½ inch space between them. If you have a small air fryer you may need to do 2 batches.
Mix up the butter mixture again and pour it all over the salmon filets. I recommend using a spatula to scrape out any seasoning that sticks to the bottom of the bowl.
Carefully place your aluminum foil “pan” into your heated air fryer and cook for 8-10 minutes or until a meat thermometer placed in the thickest part of the salmon reads at least 125 degrees Fahrenheit and the salmon flakes off easily with a fork.
Remove the aluminum foil from the air fryer and serve your salmon hot with minced parsley and lemon wedges as optional garnishes.