Crush 24 Oreo cookies into fine crumbs and mix with 5 tablespoons melted unsalted butter until resembling wet sand. Press into a 9-inch tart pan.

Melt 1 cup of caramel sauce in a saucepan over low heat for 3-5 minutes, then stir in 1 cup bittersweet chocolate chips until smooth.

Fold in 2 cups Rice Krispies cereal into chocolate-caramel mixture until evenly coated.

Pour filling into the crust and smooth it out. Press down lightly to adhere the filling.

Cover with plastic wrap and chill in the refrigerator for at least 1 hour, or up to 2 hours for optimal firmness.

Sprinkle flaky sea salt on top before serving.