Prepare the Pork: Place the pork belly on a large cutting board. Using a sharp chef's knife, slice the pork into "big chunks," approximately 1.5 to 2 inches square. Ensure they are relatively uniform in size so they cook at the same rate.

Season: If using salt, toss the chunks in a medium mixing bowl with a generous pinch of salt until evenly coated.

Load the Basket: Place the pork chunks into the air fryer basket. It is okay if they touch slightly, but do not crowd the basket in multiple layers; work in batches if necessary to ensure the air can circulate around each piece.

Air Fry: Slide the basket into the air fryer. Set the temperature to 450°F and cook for 20 minutes.

Shake (Optional): At the 10-minute mark, carefully pull out the basket and give it a firm shake to reposition the chunks. This ensures the bottom sides get as crispy as the tops.

Check for Doneness: The pork belly is finished when the fat has turned a deep golden brown and the edges look slightly charred and bubbly.

Drain and Serve: Use tongs to remove the chunks from the basket, leaving the rendered liquid fat behind. Let them sit for 2 minutes before eating, as the interior fat will be extremely hot.

Storage: Store leftovers in an airtight container in the refrigerator for up to 5 days.

Reheating: To regain the crunch, reheat in the air fryer at 400°F for 3–5 minutes.