Preheat oven to 350°F (175°C). Combine chocolate cookie crumbs with melted butter in a bowl. Press mixture into the bottom of a springform pan and bake for 10 minutes. Allow to cool.

In a mixing bowl, beat softened cream cheese with sugar until smooth. Add orange zest and juice; mix well.

Melt dark chocolate and gradually incorporate it into the cream cheese mixture until blended.

In another bowl, whip heavy cream until soft peaks form; gently fold into the chocolate mixture.

Pour filling over cooled crust and smooth the top. Refrigerate for at least four hours or overnight.

Remove from springform pan, slice generously, and garnish as desired.