If you overbeat the chocolate mixture in Step 2, beat in 2 to 3 Tbsp. more whipping cream to return mixture to a smooth consistency.
Microwave first 3 ingredients in a medium-size microwave-safe bowl at HIGH 1 to 1 1/2 minutes or until melted and smooth, stirring at 30-second intervals. Let cool 10 minutes.
Beat chocolate mixture at medium speed with an electric mixer 1 to 2 minutes or until whipped and smooth. Cover and chill 2 hours or until firm.
Shape chocolate mixture into 1-inch balls, using a small ice-cream scoop. Roll in chopped peanuts. (If chocolate mixture becomes too soft to shape, refrigerate until firm.) Place on wax paper-lined baking sheets. Chill 1 hour before serving. Store truffles in an airtight container in refrigerator up to 5 days.