Spray a 9 x 13 baking dish and set aside.

Melt the butter in a large sauce pan over medium heat. Add in the marshmallows and stir until they have melted.

Remove from heat and stir in the Apple Jacks making sure they are coated with the marshmallows.

Spread the mixture into the prepared pan and press it into a single layer.

Sprinkle with Halloween sprinkles if desired.

Allow 15-20 minutes for the treats to cool and harden then cut into 24 squares.