In a large bowl mix together mix Rice Chex, Bugles, and popcorn. Set aside.
Melt white chocolate chips in microwave for 1 minute. Stir and heat in additional 30 second increments until all the chips are melted. Be careful not to scorch!
Pour melted white chocolate over prepared snack mix. Using a rubber spatula, gently fold the mixture until completely coated.
Line a baking sheet with wax or parchment paper. Spread the white chocolate-coated mixture onto the cookie sheet. Allow the mixture to cool and dry for at least one hour or refrigerate for 30 minutes.
Once the mixture is dry, gently break it apart and place it in another large bowl. Add powdered sugar and toss until coated.
Add chow mein noodles, mini marshmallows, peanut M&M’s, and holiday sprinkles. Gently stir just until combined.