Preheat oven to 350°. Cut butter into flour until crumbly. Press into an ungreased 13×9-in. baking dish. Bake until light brown, 18-22 minutes. Cool on a wire rack.
Meanwhile, beat cream cheese and sugar until smooth. Fold in 1 cup whipped topping. Spread over cooled crust.
Beat milk and pudding mix on low speed for 2 minutes. Carefully spread over cream cheese layer. Top with remaining whipped topping. Refrigerate at least 1 hour.