Microwave chocolate and butter in large microwaveable bowl on HIGH 1 minute; stir. Repeat microwaving and stirring in 15 second intervals until chocolate is completely melted and mixture is well blended
Add nuts and broken wafers; mix well
Refrigerate 1 1/2 hours or until chocolate mixture is firm
Roll chocolate mixture into 9-inch log; wrap tightly with plastic wrap. Refrigerate 1 hour
Place unwrapped chocolate log on plate; sprinkle evenly with powdered sugar
