In a medium bowl, whip heavy cream with espresso powder until it reaches stiff peaks. Set aside.
Brew the Gourmesso espresso in the smallest serving size in your Nespresso machine.
In a small saucepan, heat milk over medium heat. Once warm, stir in vodka, Cointreau and espresso.
In a microwave safe bowl, melt chocolate in 30-second increments, stirring in between each, until melted.
Stir melted chocolate into the warm milk mixture. Pour into mug and top with whipped cream. Garnish with orange zest. Serve.