Like tea or coffee, this hot chocolate custard needs time to steep. The cocoa solids suspended in the fats in the chocolate need time to hydrate. That's why making this hot chocolate is a two-step process. You can make and refrigerate the base the day before if you'd like.
1-2Tablespoonssugar or brown sugar(to taste, and completely optional, especially if you're garnishing with marshmallows)
1egg yolk
heavy pinch of non-iodized salt(kosher, sea salt, etc)
All of chocolate base
ΒΌteaspoonpure vanilla extract or vanilla paste
Instructions
For the Base
Finely chop or grate the chocolate. Set aside.
Bring the milk and half and half to a simmer over medium heat, stirring occasionally.
Once the milk is hot, stir while slowly adding the chocolate a bit at a time. Stir until smooth.
Bring the mixture to a very slow boil/high simmer and cook for 2-3 minutes, stirring constantly. This just concentrates the mixture and thickens it up a bit. This is an optional step, but I highly recommend it.
Let this base sit for at least an hour or cool it down and refrigerate it overnight.
To Finish
In a small bowl, whisk together the whole milk and egg yolk.
Whisk this mixture into the chocolate base aong with the salt and, whisking constantly, heat the chocolate to 165F.
Taste and add the sugar (if using). Strain the mixture into a pitcher. It should be very frothy and have a nice head on it. If not, whisk and whisk until it does.
Pour into demitasse or espresso cups, garnish with coffee marshmallows (or the garnish of your choice) and indulge.