Place the meatloaf mixture, minced onion, pepperoni, tomato paste, Italian seasoning salt and pepper in a large bowl. Mix thoroughly until well combined. Divide the meat into 4 equal portions and then form the hamburgers, being careful not to over-handle the meat. One good way to do this is to throw the meat back and forth between your hands like a baseball, packing the meat each time you catch it. Flatten the balls into patties, making an indentation or divot in the center of each patty. This will help keep the burger flat as it cooks.

Split the rolls in half and brush the cut side with a little olive oil.

Pre-heat the air fryer to 370ºF.

Air-fry the burger patties for 15 minutes, flipping them over halfway through the cooking time. Spoon a little pizza sauce on each burger and top with the sliced mozzarella cheese. Air-fry at 370°F for 3 more minutes until the cheese has melted.

Remove the burgers from the air fryer and let them rest. Place the rolls, cut side up into air fryer. Air-fry at 380°F for 2 to 3 minutes to toast the rolls.

Transfer the rested burgers to the toasted rolls, sprinkle a little more Italian seasoning on top and serve immediately.