Combine 1 Cup hot water and 3 Cups milk in a pot over medium heat. Careful not bring to a full boil.
Break one Hersheys chocolate bar into little pieces and add it to the liquid. Add the 1/3 Cup of unsweetened cocoa powder and 1/2 Cup of sugar as well and stir with a whisk.
Keep stirring until all the chocolate has melted. Add a pinch of nutmeg and cinnamon to taste.
Remove from heat, and pour into mugs. Add whipped cream or marshmellows on top and sprinkle with cinnamon and cocoa powder.
Enjoy! I recommend pairing the hot cocoa with a big plate of freshly baked chocolate chip cookies :)!