In a small saucepan heat heavy cream over medium low heat. Once steam begins to rise from the cream and just before it begins to boil remove from heat and add chocolate. Let sit for about 1 minute so that the chocolate begins to soften. Then use a wire whisk or wooden spoon to stir. Keep stirring until cream and chocolate is well combined and smooth. Add desired amount to hot milk or stir in to coffee for a delicious mocha treat.