Place cookie dough, the 1/2 cup toffee pieces, and the pecans in a large resealable plastic bag and knead to combine. Press dough evenly over the bottom of an ungreased 13x9-in baking pan.
Bake for 12 to 15 minutes or until golden brown. Sprinkle with chocolate pieces immediately after baking; let stand for 5 to 10 minutes or until chocolate is softened, then spread evenly over the bars. Sprinkle with the 1/3 cup toffee pieces.