Place Chex cereal in a large bowl.
Combined powdered sugar, granulated sugar and cinnamon in a large ziplock bag.
Melt white chocolate chips in the microwave for 30 second intervals, being careful not to burn them.
Pour melted chips over Chex cereal and toss until fully coated.
Add cereal to your ziplock bag with sugar mixture, seal and shake until coated.
Pour onto a cookie sheet to let cool, if needed.
Place in a large serving bowl and toss with Cinnamon Toast Crunch cereal.