Heat the milk, heavy cream, and vanilla extract in a medium saucepan over medium heat. Do not allow the mixture to boil.
Remove the saucepan from the heat and whisk in the chocolate until melted. If needed, return the saucepan to low heat for the chocolate to melt completely.
Serve warm, in demitasse or espresso cups, topped with whipped cream and with a side of sparkling water if desired.
Notes
Unless Ghirardelli or Godiva, I do not recommend chocolate chips as they contain stabilizers and do not melt as well.
To benefit from all the benefits of cocoa, prefer organic dark rather than all other chocolates containing many more chemicals and less cocoa content.
Leftovers (if you have any) can be cooled to room temperature, then refrigerated in an airtight container or a mason jar. Reheat gently in the microwave or in a saucepan over low heat.
Are you lactose-intolerant? I recommend full-fat coconut milk for a dairy-free option that yields a similar experience. Do not use water.
If you prefer it sweeter, add sugar to taste or use milk chocolate instead.
For a thicker consistency, let the melted chocolate cool a bit and then pour into the serving cups.
If your hot chocolate is too thick, add more milk or cream.
Cooled sipping chocolate will be very thick. It will liquefy as you heat it.
I suggest small servings of this French sipping chocolate as it is quite rich. Espresso cups (or demi-tasse) is a suitable option.
This recipe yields four ½-cup servings or eight espresso-cup servings.
Nutrition information is approximate and meant as a guideline only.