For a milder onion flavor, fry the onion in 1 tablespoon butter until tender. Cool completely before adding.
Don't overmix the meat, mix just until combined.
Preheat the air fryer before adding the meatloaf.
Air Fryers can vary so be sure to use an instant read thermometer to check the internal temperature of the meatloaf and ensure it reaches 165° F.
Check the meatloaf early to ensure it doesn't overcook. Add more time as needed.
Rest the meatloaf before slicing so it doesn't fall apart.