Remove crisper tray from the air fryer and insert the air fryer rack. Place crisper tray on top of rack. Preheat the air fryer on air broil to 400°F.
Form 1 pound ground beef into 3-4 hamburger patties about half an inch thick.
Season each hamburger patty evenly with chili seasoning on both sides. 1 Tablespoon chili seasoning will be enough to season all patties on both sides. Adjust seasoning to your liking as needed.
Make a small indent in the middle of the patty with your thumb.
Spray both sides of hamburger patties with avocado oil spray lightly to coat.
When air fryer is preheated, place hamburger patties in the air fryer basket in a single layer.
Air fry 6 minutes. After 6 minutes, turn each hamburger patty over and continue to air fry on air broil for 3-4 minutes or until the internal temperature of the hamburger patties reaches 145-160°F when checked with an instant read thermometer depending on your desired doneness.
If using, place a slice of cheese on each hamburger patty (3-4 slices cheese total) and close the air fryer basket. Leave basket closed for about 30 seconds to a minute to melt the cheese. Once cheese is melted, remove hamburgers from air fryer and set aside to rest.
Carefully wipe the crisper plate if you prefer to clean it, and place 3-4 hamburger buns in the air fryer basket in a single layer with insides of bun facing up, so the inside gets toasted. Air fry at 400°F for 2 minutes until buns are toasted to your liking. Continue with remaining buns as needed.
Place hamburger patties on buns and top with big mac sauce and toppings of your choice, such as lettuce, pickles, red onions, and tomatoes.