In microwave safe bowl add butter, chocolate chips, peanut butter, and vanilla

Microwave and mx in cycles until fully melted

In large bowl toss together melted mix and chex until evenly coated

In a gallon sized ziplock bag add powdered sugar and mixture and shake to coat

Make sure to leave enough room in ziplock bag to be able to shake well. It is best to do this step in several small to medium batches