Press the center of the bread slice down with the back of a spoon to create a shallow well. Do not break through the bread.
Spread the softened butter lightly around the edges of the bread.
Place the bread into the air fryer basket carefully.
Crack the egg into the indentation. Season the egg with salt and pepper.
Sprinkle the shredded cheese around the egg on the buttered edges.
Air Fry at 350°F (175°C) for 6 to 8 minutes, until the egg white is set and the toast is golden brown.
Remove carefully with a spatula and serve warm.