Preheat the oven to 350 degrees F. In a small bowl, stir the Oreo crumbs and butter until combined. Press the mixture onto the bottom and up the sides of a 9-inch deep-dish pie pan; freeze until set (15 minutes). Bake for 10 minutes; let cool.
PREPARE THE PUMPKIN LAYER:
Meanwhile in a large bowl, whisk together the 3 eggs, 1 cup cream, pumpkin, brown sugar, spice and salt until just combined. Pour into the cooled pie shell and bake until set, 40 to 45 minutes. When you shake the pan, the filling should no longer be jiggly. Let the pie cool at room temperature slightly, then refrigerate for at least 3 hours, or overnight.
PREPARE THE CARAMEL LAYER:
In a glass bowl, microwave the caramels with 1/2 cup cream until melted, 2 to 3 minutes- adding 1 minute increments, if needed, if they are still not completely melted. Stir until smooth, then let cool to room temperature. The caramel mixture must be COMPLETELY COOLED before adding to the whipped cream in the next step.
Using an electric mixer, whip the remaining 1 1/4 cups cream until soft peaks form. Drizzle in the cooled caramel and beat until well blended. Spoon the caramel whipped cream on top of the pumpkin filling and refrigerate until completely chilled.
ADD THE TOPPING:
Before serving, coarsely grate the chocolate on top of the pie.
Notes
*If your pie cracks on the surface while baking, don't worry about it- you'll be covering that up with the caramel whipped cream!
*Don't have any pumpkin pie spice? Make your own by mixing equal parts of cinnamon, ginger, allspice and nutmeg.
*Stick toothpicks in the top of any leftover pie before you cover with plastic wrap (keep stored in the refrigerator).