Begin by peeling the fresh orange, ensuring to avoid the bitter white pith. Juice the orange and set the juice aside for later.

In a medium saucepan, combine the whole milk with the orange peel and bring to a gentle simmer over medium heat. Allow the milk to infuse for about 10 to 15 minutes.

Reduce the heat to low and add the chopped semi-sweet or dark chocolate, unsweetened cocoa powder, caster sugar, and cinnamon to the infused milk. Stir continuously until the chocolate is completely melted.

Once the chocolate mixture is smooth and velvety, slowly stir in the reserved fresh orange juice. Heat for an additional minute.

Pour the prepared Orange Hot Chocolate into mugs and garnish with cocoa powder, fresh orange zest, and whipped cream, if desired.