In a 2-cup glass measuring cup, add the milk and chocolate syrup. Stir until well mixed.
Heat the mixture in the microwave for about a minute and a half until hot and starting to bubble. Watch closely so it doesn't overflow the measuring cup.
Pour the dry hot chocolate mix into a large mug and add the hot milk. Stir until dry mix is incorporated.
Using a frother, froth the milk until foamy. Pour the coffee into the mug. Add a drop of peppermint extract and marshmallows if desired. Enjoy!