Preheat oven as per brownie mix instructions. Prepare brownie batter and pour into a greased baking dish. Bake for 20-25 minutes until a toothpick comes out with moist crumbs. Cool in pan for at least 1 hour.

In a mixing bowl, beat softened cream cheese with an electric mixer until smooth and creamy. Fold in thawed whipped topping until fully incorporated.

Whisk together chocolate pudding mix and milk in a separate bowl until thickened. Let sit for 5 minutes to improve consistency.

Spread the cream cheese mixture over the cooled brownie base. Pour chocolate pudding layer on top, smoothing with a spatula. Top with remaining whipped topping.

Cover with plastic wrap and refrigerate for at least 2 hours or overnight to allow flavors to meld and layers to set.

Slice the cake into squares, wiping the knife between cuts for clean edges and serving.