Finely crush the Oreos with a food processor or blender.
Stir crumbs together with 8 tablespoons (113g) melted butter until well combined.
Press into the bottom and sides of a 10-inch pie pan. Freeze crust for 10 minutes until set.
Combine remaining 8 tablespoons butter and brown sugar in a small saucepan. Cook over medium heat, whisking constantly, until mixture begins to bubble. Continue cooking, whisking constantly, for 1 minute.
Remove from heat. Slowly whisk in 1/4 cup (60g) heavy whipping cream until smooth. Cool caramel about 15 minutes.
Pour the caramel over the Oreo crust, then return to freezer for about 30-45 minutes until just chilled and set. (You don't want the caramel to fully freeze.)
Place chocolate chips in a bowl.
In a saucepan, bring 1 cup (235g) heavy whipping cream to a simmer over medium-high heat. Pour the cream over the chocolate chips and let sit for 5 minutes, then whisk until completely smooth.
Pour the chocolate over the caramel and freeze for a final 30 minutes, until just chilled and set. OR refrigerate, covered, until ready to serve. Before serving, sprinkle the top with a flaky sea salt like kosher salt.
Store covered in the refrigerator and serve chilled.