Place the chocolate, sugar, cocoa powder, instant coffee granules, and 1 cup milk in a small sauce pot. Warm over medium heat and stir until the chocolate has melted into the milk. Once smooth, remove from heat. Do not let the mixture boil.
Pour the chocolate mixture into a blender. Add the remaining milk to the blender, along with the vanilla extract and ice. Cover and blend until very smooth.
Pour into glasses and add whipped cream and garnishes if desired!