Line a 9x9-inch pan with aluminum foil for easier cleanup and spray with cooking spray; set aside.

To the canister of a food processer, add the Oreos (whole) and process on high speed until you have fine crumbs; set aside.

To a small microwave-safe bowl, add 0.25 cup butter, 1 tablespoon dark chocolate, and heat on high power until the chocolate and butter have melted and can be stirred smooth.

Pour melted chocolate and butter mixture into the food processor, process on high speed to incorporate, turn crumb mixture out into the prepared pan, and hard-pack the mixture to form and even flat crust layer; set aside.

To a large mixing bowl, add the 4 ounces cream cheese, and beat with a handheld electric mixer on high speed until fluffy; set aside.

To a separate, large, microwave-safe bowl, add the 8 ounces chopped dark chocolate, 0.75 cup heavy cream, and heat in 30-second increments until the chocolate has melted and can be stirred smooth into the cream and mixture is silky, likely about 90 seconds total, but microwaves vary and you don't want to scorch your mixture.

Transfer the creamy chocolate mixture into the bowl with the cream cheese and beat on high power until smooth and combined.

Optionally add the 1 tablespoon liquor and/or 0.5 teaspoon salt. The salt is highly recommended to complement chocolate flavors and balance richness.

Evenly spread the mixture over the crust.

Evenly sprinkle with the 0.5 cup mini chocolate chips and refrigerate for at least 3 hours, or overnight or a few days in advance, before slicing and serving. After the 3-hour point when dessert is well chilled, cover with foil when dessert is in the fridge. Initially, there will be some heat which will create condensation and that's why initially you don't want to cover it but after it's sufficiently chilled, yes cover it.