Heat ove to 350. Spray a 9 x 13" pan w/ cooking spray. In lg bowl, combine cake mix, melted butter, 1/3 cup evaporated milk and pecans. Mix until dough forms. Press 1/2 the dough into bottom of pan, bake 6 min. Reserve remaining dough. In microwaveable bowl, microwave caramel candies w/ 1/3 cup evaporated milk, stirring often, until smooth. Sprinkle chocolate chips over warm baked dough. Spread caramel mix over chocolate chips. Crumble remaining dough over caramel mix. Bake 20 min. Cool.