1. In small saucepan over low, blend first 4 ingredients and heat, stirring, until smooth and melted. Refrigerate until cold.
2. Beat whipping cream until just beginning to thicken just a little. Add chocolate mixture gradually while continuing to beat. Beat until mixture will mound. Chill.
3. Heat milk in heavy saucepan. Pour 6oz (175mL) milk into mugs and add chocolate mixture to taste (about 4 heaping tbsp per mug).