Grease a 9x13 inch baking dish or line it with parchment paper.

In a medium saucepan, combine the granulated sugar and light corn syrup. Heat over medium heat, stirring until the sugar dissolves and the mixture starts to boil.

Remove the pan from the heat and stir in the creamy peanut butter.

Add the vanilla extract to the mixture.

In a large mixing bowl, pour the melted mixture over the Special K cereal. Stir until all the cereal is evenly coated.

Transfer the cereal mixture to the prepared baking dish and press it down firmly.

If using chocolate chips, sprinkle them over the top and gently press them into the mixture.

Allow the bars to cool at room temperature for at least an hour.