Grease a ramekin with a drop of oil (or use a spray) and spread with a finger or pastry brush.
Add ½ teaspoon of cold water.
Gently crack egg into ramekin.
Season with salt and pepper.
Top with grated cheese to cover surface.
Place ramekin in air fryer (no need to preheat) at 180C for 7 – 8 minutes (or until egg white is cooked and yolk runny or to your preference). See notes for baking more than one egg.
Lift the ramekin out of the air fryer and allow to rest for one minute (the egg will carry on cooking).
Run a palette knife (or similar) around the outside of the egg and lift out of the ramekin (using oven gloves). Alternatively serve in the ramekin.
Serve on its own or with buttered toast and garnish with chives or your favourite sauce etc.