Heat milk or half and half over medium-low heat in a heavy saucepan. Whisk in the Spicy Mexican Chocolate Sauce. Continue to stir until the hot chocolate just comes to a simmer, do not allow to come to a boil.
Serve topped with sweetened whipped cream and garnish with cinnamon and chocolate curls made by running a vegetable peeler along the side of a chunk or bar of good quality chocolate.