1In large bowl, place cereal. In small microwavable bowl, microwave butter uncovered on High about 30 seconds or until melted. Stir in espresso; add chocolate chips. Microwave on High 30 seconds; stir. Continue microwaving and stirring until mixture is smooth. Pour chocolate mixture over cereal; toss until well coated.
2In large resealable food-storage plastic bag, mix powdered sugar and cocoa. Add cereal mixture and pound cake pieces; shake until evenly coated. Serve in individual bowls or glasses. Top with dollops of mascarpone cheese.