In a large zippered bag combine the cake mix and powdered sugar and shake to mix well.
Melt the white chips in the microwave by heating for 30 seconds then stirring and repeating until melted and smooth.
Put the cereal in a large bowl, pour the melted chocolate over it and mix until well coated.
Add the cereal mixture to the plastic bag and shake until the cereal is completely covered.
Add any additonal candy decorations if desired.