In a microwave-safe bowl, combine the semi-sweet chocolate chips and creamy peanut butter. Heat in the microwave in 30-second intervals, stirring until smooth and melted.

Stir in the peppermint extract into the melted mixture, blending well until the heavenly aroma of mint fills the air.

Pour the chocolate-peanut butter mixture over the Chex cereal in a large bowl. Gently stir until every piece is thoroughly coated and shiny.

Carefully transfer the chocolate-coated Chex cereal into a large zip-top bag or bowl.

Add the powdered sugar to the bag or bowl. Seal securely and shake, or stir until all the pieces are well-coated.

Gently fold in the mint chocolate candies, allowing them to mingle with the cereal mixture.

Spread the mixture onto a baking sheet, allowing it to cool down completely before serving.