Combine graham cracker crumbs and melted butter until throughly mixed.
Press crumb mixture into a 13x9 baking dish using the bottom of a measuring cup. Refrigerate crust for 10 minutes.
In a medium bowl, beat cream cheese until fluffy. Add in the 2 tablespoons of milk and the sugar. Mix well.
Fold half of the Cool Whip (8 ounces) into the cream cheese mixture, and spread over the top of the crust. Refrigerate 10 minutes.
While cream cheese is setting, add both boxes of pudding mix and 2 3/4 cups of milk to a bowl. Whisk until it begins to thicken. Refrigerate 5 minutes.
Spread pudding mixture over the top of the cream cheese layer. Refrigerate for 30 minutes.
Spread remaining 8 ounces of Cool Whip over the top of the pudding layer.
Draw lines of chocolate syrup across the top. Run a knife down the top in the opposite direction of the syrup lines, about an inch or so apart. Sprinkle with crushed pistachios.
Refrigerate for at least 2 hours to let everything firm up. Overnight is even better.
Video
Notes
Put two tablespoons of pistachios in a sandwich bag and beat with a meat mallet. You don't want "dust", but smallish chopped pieces. I used a tablespoon to sprinkle over the whole dessert.