Grease an 8"x8" baking pan with cooking spray.
In a large mixing bowl, mix together the cereal, peanuts, and candy corn.
In a small saucepan over low to medium heat on the stovetop, melt the peanut butter and corn syrup, constantly stirring to keep it from scorching on the bottom of the pan.
Cook for about 5 to 10 minutes, constantly stirring. The peanut butter and corn syrup will melt together and form more of a syrupy liquid.
Remove the peanut butter mixture from the stove, give it a good stir, and pour it over the cereal mixture.
Stir everything together really well, making sure all of the cereal, peanuts, and candy corn are coated with the peanut butter syrup.
Spread the mixture in the greased dish, and firmly pat it evenly into the pan.
Allow the treats to cool. Then slice the bars for serving.
Drizzle the top of each bar with melted white chocolate, and add a piece of candy corn for decoration.