Heat the milk in a saucepan over medium-high heat and bring just to a simmer. Take off the heat and stir in the chocolate, vanilla, and maraschino cherry liquid until the chocolate is fully melted. Let the mixture sit off the heat for 5 minutes, allowing the flavors to meld. Reheat the mixture over low heat until it comes to a simmer, stir in the coffee liqueur and serve with a dollop of whipped cream, a dusting of cocoa powder and a maraschino cherry.