Preheat the air fryer to 375°F. Lightly spray the air fryer basket with cooking spray.
Season both sides of the chicken breasts with salt and pepper.
In a mixing bowl, combine chopped broccoli, shredded cheddar, mayonnaise, and minced garlic. Mix until well combined.
Divide the broccoli cheddar mixture among the chicken breasts, spreading it on top evenly.
In a separate bowl, mix panko breadcrumbs with melted butter and dried parsley. Sprinkle this mixture over the broccoli cheddar topped chicken breasts, pressing down slightly to adhere.
Place the chicken breasts in the air fryer basket in a single layer. Cook for 15-20 minutes, or until the chicken reaches an internal temperature of 165°F and the topping is golden brown.
Once cooked, carefully remove the chicken from the air fryer and let it rest for a few minutes. Serve hot with your favorite sides.