Preheat oven to 375°F (190°C) and grease a 9x13-inch baking dish.
Spread the cubed chicken evenly in the bottom of the dish.
In a bowl, mix the Parmesan, spinach, and artichokes.
In another bowl, whisk together the sour cream, cream cheese, mayo, and garlic. Stir this into the spinach mixture.
Spoon the cheesy mixture over the chicken and spread it evenly.
Mix crushed corn flakes with melted butter and sprinkle over the top.
Bake for 30 minutes, until bubbly and golden on top.
Let cool for 5 minutes before serving.