Line the bottom of a greased 13x9-in. baking dish with parchment; grease parchment. Set aside. , In a large bowl, beat the pumpkin, milk, sugar, eggs and vanilla until well blended. Pour into prepared pan. Sprinkle with cake mix and drizzle with butter. Sprinkle with pecans., Bake at 350° for 1 hour or until golden brown. Cool completely in pan on a wire rack. Invert onto a large serving platter; carefully remove parchment., In a large bowl, beat the cream cheese, confectioners' sugar and vanilla until smooth. Fold in whipped topping. Frost dessert. Store in the refrigerator.