Build the brown butter crust
1-Heat the butter in a small saucepan: Heat the butter in a small saucepan over medium heat until it turns fragrant and amber, indicating the brown butter flavor is ready. Remove from heat immediately.
2-Stir the melted brown butter into the: Stir the melted brown butter into the flour and finely chopped pecans until the mixture resembles damp sand. Press it firmly and evenly into a greased 9×13-inch pan, ensuring the corners are well-filled.
3-Bake at 325 degrees F for 25: Bake at 325 degrees F for 25 minutes until the top is lightly golden. Set the pan aside and let the crust cool completely to room temperature before adding layers.

Whip the cream cheese layer
4-Beat the room-temperature cream cheese and powdered: Beat the room-temperature cream cheese and powdered sugar until smooth and fluffy. Gently fold in 8 oz (half) of the whipped topping until you have a spreadable cloud-like consistency.
5-Spoon dollops of the cream cheese mixture: Spoon dollops of the cream cheese mixture over the cooled crust. Use a light hand to spread the mixture to the edges, creating an even seal that prevents the pudding from soaking into the crust.

Mix and set the chocolate pudding layer
6-Whisk both boxes of chocolate pudding mix: Whisk both boxes of chocolate pudding mix with 3 cups of cold milk until glossy and thickened. Let the mixture chill briefly in the fridge to start holding its shape.
7-Pour the pudding over the cream cheese: Pour the pudding over the cream cheese layer and level it gently. Chill the pan until the pudding surface looks set and slightly bouncy when tapped.

Finish, garnish, and chill
8-Spread the remaining 8 oz of whipped: Spread the remaining 8 oz of whipped topping over the pudding layer in a light, even blanket. Garnish with chopped nuts or a dusting of cocoa powder as desired.
9-Chill the entire dessert in the refrigerator: Chill the entire dessert in the refrigerator for at least 4 hours before serving to ensure the layers are cold, stable, and easy to slice.