Place the powdered sugar, granulated sugar, and 2 teaspoons of the cinnamon in a gallon size ziploc bag; set aside.
Line a rimmed baking sheet with parchment paper; set aside.
Place the Rice Chex cereal in a large bowl.
Melt the CandyQuick in a medium bowl in the microwave according to the package directions. Once completely melted and smooth, stir in the the remaining 2 teaspoons cinnamon and vanilla extract, and immediately pour over the Rice Chex. Using a rubber spatula, gently stir until all of the cereal is evenly coated.
Transfer the coated cereal to the ziploc bag with the cinnamon sugar mixture. Seal the bag and shake until all of the cereal is coated with the sugar mixture. Turn the cereal out onto the prepared baking sheet and spread into an even layer. Refrigerate for 30 minutes, or until set. Store in an airtight container in the refrigerator for up to 1 month.