Put a mason jar in the freezer (this is for making the cream topping. If you'd rather use whipped cream, skip this step).
Make a pot of strong coffee.
While the coffee is brewing, make yourself a batch of hot chocolate. We recommend something homemade and creamy, but any hot chocolate will work.
Pour your hot chocolate into the bottom 1/3rd of your mug.
Pour your coffee over the back of a spoon into the mug, filling to 2/3rds full.
Put your heavy cream into the chilled mason jar and close.
Shake until the cream thickens slightly.
Pour cream over the back of a spoon, filling the mug completely.
Top with chocolate shavings.