Gather everything you need! Measure 9 cups of Chex Cereal in a bowl. Mix (1/4 cup) butter, (1 cup) chocolate chips, and (1/2 cup) peanut butter in a microwaveable bowl. Heat in microwave for about 30 seconds. After heating, add (1 tsp) vanilla extract and stir together. Pour mixture over cereal. Mix cereal until evenly coated! Put the mixture into a Ziploc bag (1 Gallon). Add powdered sugar (1 & 1/2 cup), seal the bag and shake! Lastly, let cool in the refrigerator.