Use smooth peanut butter for the best coating and texture. Microwave in short intervals when melting chocolate and butter to prevent burning. Ensure the cereal is completely dry before adding the chocolate mixture to avoid sogginess. If you don’t have powdered sugar, you can pulse granulated sugar in a blender to make your own. Use a large bowl or resealable bag for coating with powdered sugar to minimize mess. For an even coating, shake the bag/container for at least 1-2 minutes. Allow Puppy Chow to cool completely before storing to keep it crisp. Store in an airtight container at room temperature for up to two weeks or freeze for up to 3 months.