Combine the peanut butter, butter, chocolate chips, and vanilla in a microwave-safe bowl and microwave for one minute. Stir thoroughly. Then microwave for one more minute. Stir again. Place Chex in a large bowl. Pour the mixture over the Chex and mix thoroughly. Using a large Ziploc bag or re-sealable container, add the powdered sugar, then the covered Chex mixture. Shake it all up until coated. If you would like to add some color, be sure to add that to your sugar before coating!

Refrigerate for 1 hour, then serve or pour into your holiday treat bags for fun, homemade gifts!