Mix flour, butter and nuts. Press into a 9 x 13" baking dish. Bake in a 400 degree oven for 10 to 15 minutes until browned. Cool. Combine one container of whipped topping with the powdered sugar and cream cheese. Spread over cooled crust. Mix 1 1/2 cup cold milk with chocolate pudding and spread over the cream cheese layer. Mix 1 1/2 cups cold milk with vanilla pudding and spread over the cream cheese layer. Top with one container of whipped topping and sprinkle nuts over the top.