Heat ½ cup cream in a heavy non-reactive saucepot over moderate heat until cream comes to a low boil.
Remove the pan from the heat and add chocolate and let chocolate stand in hot cream for 3 to 5 minutes to soften, then whisk the chocolate together with the cream.
Stir in Bailey’s Hazelnut Liqueur (if using) and transfer the fondue to a fondue pot with a flameIf the fondue becomes too thick, stir in reserved cream, 1 tablespoon at a time until the chocolate is smooth and has a creamy consistency.
Serve with your favorite dippables.