To make the Sprinkle Rim:

Cup of Yum
1. Place the dark chocolate in a shallow, wide bowl and heat in the microwave in 20 second increments, stirring in between, until melted and smooth.
2. Place the sprinkles in another shallow wide bowl or rimmed plate.
3. Dip the top of each heat-safe glass in the melted chocolate, then immediately coat in the sprinkles.
4. Set aside while you prepare the hot cocoa.

To make the Dark Hot Cocoa:

1. In a medium saucepan, whisk together the sugar, black cocoa powder, salt, and water.
2. Bring to a simmer over medium heat and cook, whisking often, until all the powder has dissolved.
3. Slowly whisk in the milk and continue to cook until heated through.
4. Remove from heat and whisk in the vanilla extract.
5. Serve immediately in sprinkle-rimmed heat-safe glasses if desired.