In a large mixing bowl, beat together 12 ounces cream cheese, ½ cup powdered sugar, and ½ cup cocoa powder until smooth and fluffy.
Gently fold in 8 ounces thawed Cool Whip until fully combined.
Place a single layer of the 16-ounce package chocolate graham crackers in the bottom of an 8x8-inch or 9x9-inch baking dish.
Then top with 1/3 of the cream cheese mixture spreading it evenly over the top.
Continue layering 2 more times.
To make the ganache topping, combine ½ cup heavy whipping cream and 1 cup chocolate chips in a microwave-safe bowl. Microwave in 30-second intervals, stirring between each interval, until the chocolate chips are melted and the mixture is smooth.
Pour the ganache topping evenly over the cake.
Refrigerate for 4-5 hours (overnight is preferred) until the graham crackers have softened.
Top with the mini chocolate chips if preferred. Serve and enjoy!