Prepare a 9 or 10 inch springform pan by lining the sides with wax paper. Make the crust by grinding the sandwich cookies into fine crumbs in a blender or food processor. Combine with melted butter, then press into the bottom of the prepared pan. Set aside in the refrigerator.

To make the cheesecake, whip the cream until soft peaks form, then set the whipped cream aside. In a small bowl, microwave the dark chocolate at 30 second intervals, stirring in between until it is melted and smooth. Allow it to cool slightly while you continue with the cheesecake mixture. Beat the cream cheese, sugar, vanilla, salt, and lemon juice until no lumps remain. You will need to scrape down the sides of your bowl often to get the cream cheese mixture completely smooth. Once smooth, add the melted chocolate and cocoa powder and blend, scraping down the sides several more times, until color and texture are smooth and consistent. Use a rubber spatula to fold in the whipped cream you set aside. Once the mixture is thoroughly combined, spread it evenly into your prepared crust and cool in the fridge for about 4 hours.

To make the salted caramel topping, melt butter in a small saucepan. Stir in brown sugar until dissolved, then whisk in cream. Bring to a boil and cook, stirring constantly, for 3 minutes. Remove from heat and let it cool for about 15 minutes. When it is cool enough to use you should be able to stick your finger in it without burning yourself. Drizzle cooled caramel over chilled cheesecake and sprinkle coarse salt over it to taste.