Preheat oven to 325 degrees F (165 degrees C). Grease and flour 3 (8 inch) pans.
In a large bowl, combine cake mix, milk, eggs, oil and instant vanilla pudding mix. Beat on low speed until blended. Scrape bowl, and beat 4 minutes on medium speed. Pour batter into prepared pans.
Bake in the preheated oven for 20 to 25 minutes, or until a toothpick inserted into the center of the cake comes out clean. Allow to cool.
To make the frosting: In a large bowl, beat the cream cheese with the white sugar and confectioners' sugar until smooth. Fold in the whipped topping, pecans and chopped chocolate. Spread between layers and on top and sides of cake.