Preheat your air fryer to 375°F (190°C). If it doesn't preheat, just let it run empty for 3 minutes.
Butter one side of each slice of bread. Think of it as giving the bread a spa day.
Place cheese slices between the unbuttered sides of the bread, like a sandwich—because it is one.
Carefully place the sandwich into the air fryer basket. Buttered sides face out.
Air fry for 4–5 minutes, then flip carefully with tongs.
Cook for another 3–4 minutes until both sides are golden brown and crispy.
Remove, let it sit a minute (if you can resist), then slice and enjoy.