Prep the chicken: Pat the chicken breasts dry with paper towels. On a cutting board, use a sharp knife to cut a deep pocket into the thickest side of each breast. Keep the knife parallel to the board and stop about 1/2 inch from the opposite side so you don’t cut through.

Season the outside: In a small bowl, mix salt, pepper, garlic powder, onion powder, and paprika. Rub the chicken with a little oil, then sprinkle the spice mix evenly over both sides.

Make the filling: In a medium bowl, combine cream cheese, mozzarella, Parmesan, spinach, garlic, parsley, lemon zest, and a pinch of red pepper flakes if you like. Stir until smooth and evenly mixed. Taste and adjust salt and pepper.

Stuff the chicken: Spoon the filling into each pocket. Don’t overfill—about 2–3 tablespoons per breast usually fits. Press the pocket closed and secure with 2–3 toothpicks each to keep the filling inside.

Preheat the air fryer: Set it to 375°F (190°C) for 3–5 minutes. Lightly spray the basket with nonstick spray.

Air fry: Arrange the stuffed breasts in a single layer with space between them. Air fry for 16–20 minutes, flipping once halfway through. Cook until the thickest part reaches 165°F (74°C) on an instant-read thermometer.

Rest and remove toothpicks: Let chicken rest 5 minutes so the juices settle. Carefully remove the toothpicks before serving.

Serve: Spoon any juices from the basket over the chicken. Add a squeeze of lemon and serve with a simple side like roasted vegetables, a green salad, or garlic mashed potatoes.