Step 1Heat the oven to 350 degrees.
Step 2Mix the flour, butter and pecans with your fingers until the ingredients come together in a soft dough. Press the dough into the bottom of a 13-x9-inch baking pan; the crust will be very thin. Bake until the crust is a pale golden brown, 15 to 20 minutes. Cool on a wire rack.
Step 1Mix the cream cheese, powdered sugar and 1 cup of the whipped topping. Carefully place small amounts of it across the cooled crust, then gently spread them in a thin layer. It's OK if you pull up a little of the crust as you go.
Step 2Mix the chocolate pudding mixes and the milk together. Place small amounts of the pudding across the cream cheese layer, then carefully spread them in the same manner to the edges of the pan. Spread the remaining whipped topping on as the third layer.
Step 3Cover the dessert and chill it at least 2 hours. To serve, cut the dessert into squares and lift from the pan with a pie server or spatula.