Make Layer 1 (the Crust): Preheat oven to 350 degrees F. In a medium bowl, stir together the flour, pecans and butter until the mixture is evenly moistened. Press evenly into the bottom of a 9x13-inch pan. Cook for 20 minutes, then allow to cool completely.
Make Layer 2: Using an electric mixer, beat together the cream cheese and powdered sugar until smooth and blended. Spread in an even layer over the cooled crust.
Make Layer 3: Spread the Cool Whip over the cream cheese layer.
Make Layer 4: In a medium bowl, whisk together the milk and the packages of chocolate pudding mix for 2 minutes, until thick and smooth. Spread in an even layer over the Cool Whip. (It may mix a little with the Cool Whip, that's okay!)
Make Layer 5: In a medium bowl, whisk together the milk and the packages of French vanilla pudding mix for 2 minutes, until thick and smooth. Spread in an even layer over the chocolate pudding layer.
Make Layer 6: Spread the container of Cool Whip evenly over the top of the French vanilla pudding layer. Garnish with mini chocolate chips and chopped pecans, if desired.
Refrigerate for at least 30 minutes before serving. Leftover cake can be stored, covered, in the refrigerator for up to 4 days.