1In large microwaveable bowl, measure cereal. Set aside
2In 2-cup microwavable measuring cup, heat butter and chocolate chips on High 1 minute or until almost melted; stir and microwave another 30 seconds or until mixture can be stirred smooth; stir in condensed milk, heat 30 seconds or until boiling; stir in cinnamon. Pour over cereal mixture, stirring until evenly coated.
3Microwave on High about 3 minutes, stirring every minute, until mixture is glazed. Stir in coconut and marshmallows. Pour onto waxed-paper lined pan to cool.