Preheat oven to 350 degrees F.
Pour cornflakes in a bowl.
Crush cornflakes with the back of a measuring spoon. Kids will love to help with this step.
Gather dry ranch dressing mix and grated Parmesan cheese and add to cornflakes.
Cut chicken breasts into smaller chunks.
Dip chicken in butter, then cornflake mixture. Coat well and place in a greased 13x9 baking dish.
Place dish in the oven for 45 minutes.
Serve and enjoy!