Crush the Oreos in a plastic bag with a rolling pin or in a food processor.
Add the butter and press firmly into the bottom of a pie or tart pan.
Beat 1 ½ cups of the cream until stiff peaks form. Set aside.
Combine the 6 tablespoons of cream and chocolate in a microwave safe bowl and microwave on low power, stirring every 30 seconds until the chocolate is completely melted.
Whisk about ⅓ of the whipped cream into the chocolate.
Gently fold all of the chocolate mixture into the remaining whipped cream.
Pour into the prepared crust and chill for at least 6 hours.
Top with desired toppings.
