Preheat air fryer to 390 degrees. Line air fryer pan or basket with aluminum foil
In a large bowl, mix together ground chuck, onion, almond flour, cheese, eggs, ½ can of tomato sauce, 1 tablespoon dijon mustard, 1 tablespoon Worcestershire sauce, salt, and pepper.
Place the meat mixture on foil and Shape it into a loaf.
Cook for 25 minutes (maybe more for a thicker loaf or depending on the wattage of the air fryer.) Check the internal temperature for 160 degrees
Add dijon mustard, and add Worcestershire sauce. Meanwhile, mix together the remaining tomato sauce.
When the meatloaf is almost done, brush sauce over the meatloaf. After that, cook for an additional 5 minutes or until the internal temperature reaches 165 degrees.