Pour milk into a medium saucepan. Whisk in cocoa powder and sugar until well combined and most lumps have disappeared.
Heat over medium heat until hot, continuing to whisk. Do not boil.
If using, add chopped chocolate and vanilla. Whisk until smooth.
Divide cocoa between 2 to 3 mugs. Serve plain or with your favorite toppings, such as whipped cream or marshmallows. Enjoy!
Notes
This recipe makes 3 small servings or 2 larger servings. To serve a crowd, simply double, triple, or even quadruple the recipe.Although other types of milk will work, for richest results, use whole milk.For a vegan option, substitute your favorite plant-based milk. Creamier options, like oat, coconut, or soy, will work best.Make sure to read all the info before this recipe card for tons of tips, variations, topping ideas, and more!