We came by this Tres Leches Hot Chocolate idea to use up all the milk varieties in our fridge. We fell in love with it so much, it's our house hot chocolate now. Make this with plant-based milks or cow's milk or both. You choose. This recipe easily scales up for more cups. Note: this makes 1 small cup of hot chocolate (1/2 cup).
Choose 3 milk varieties and pour into a liquid measuring cup, varying milk proportions to your liking. Set aside.
In a small saucepan, whisk together the sugar, cocoa powder, pinch of salt, and dash of cinnamon. Pour in about 1 tablespoon of the milk (you can eyeball this), and whisk into a smooth paste before whisking in the remainder of the milk until smooth. This method will keep the lumpy hot chocolate at bay.
Turn heat to medium and bring to a simmer, stirring occasionally, until hot. Immediately pour into a mug and serve. Add marshmallows if desired. For tiny humans, add an ice cube or a cold glug of milk to quickly cool.