In medium saucepan, bring first 5 ingredients and large pinch of cayenne to boil over medium-high, whisking constantly. Whisk in 2 tbsp. liqueur or 1/2 tbsp. sugar. In medium bowl, whisk cream with remaining 2 tbsp. liqueur or 1/2 tbsp. sugar until stiff peaks form. Divide hot chocolate between mugs. Top each with whipped cream and pinch of cayenne.
Add a dollop of our Chocolaty Whipped Cream for an extra-indulgent treat.
The Do's and Don'ts of Cooking with Chocolate