Add the melted chocolate to the bowl of cereal and gently stir with a rubber spatula until evenly coated. Sprinkle on the powdered vanilla and chocolate pudding mixes and toss until coated.
Leftover snack mix can be stored to be eaten later however, the popcorn will likely go stale. To skip out on stale popcorn, you can remove it from the mix before storing it in an airtight container or Ziploc bag.