Prepare the pan by lining a 9x9-inch pan with aluminum foil and spraying lightly with cooking spray.

In a food processor, crush about 24 Oreo cookies into fine crumbs. Mix melted butter with dark chocolate, pour into cookie crumbs, and blend.

Press the crust mixture into the prepared pan evenly and firmly across the bottom.

Beat softened cream cheese on medium speed until light and fluffy, about 2-3 minutes.

Melt dark chocolate and heavy cream in 30-second intervals until smooth. Stir between each interval.

Once melted, cool slightly and add to the cream cheese, beating until smooth.

Add optional Baileys or Kahlua and salt, mixing until smooth.

Spread the filling over the crust evenly, smoothing out the top.

Garnish with mini chocolate chips and refrigerate for at least 3 hours to set.

Slice into squares and serve chilled, optionally with whipped cream or fresh berries.