Place a stockpot with the milk and heavy cream over med-high heat. When the milk begins to steam, don't let the milk come to a boil, whisk in the unsweetened cocoa, sugar, pure vanilla extract, and ground cinnamon.

Continue to whisk until the ingredients are completely dissolved into the milk and heavy cream mixture. 

Remove the stockpot from the heat. Ladle the hot chocolate into mugs and top with marshmallows as you want and drape with drizzles of milk chocolate, dark chocolate, or white chocolate syrup. 

Add the gingerbread man sprinkles.

Serve.