Peel and slice apples. Place apples in a large bowl.
Add the ⅔ cup brown sugar, lemon zest and juice from half the lemon, nutmeg and cornstarch. Mix well.
Pour the apples into a 9 x 9 baking pan that has been sprayed with non-stick spray.
Place 4 cups of Corn Flakes Cereal in a zip-loc bag. Seal and crush the cereal into small pices.
Add ⅓ cup brown sugar and melted butter to the cereal, re-seal and mix well squishing with your hands.
Sprinkle the topping over the apples. Bake 35 - 45 minutes or until golden brown and the apples are cooked.
Serve warm with ice cream!
One thing, I would suggest serving this dessert within a few hours of removing it from the oven. In my opinion, it is best when served warm. If you serve it the next day you might notice the cereal topping has become a bit chewy and no longer has a crunch to it. It is still good, just not the same.