Heat oven to 375°F (350°F for dark or nonstick pan). Grease or spray 13x9-inch pan. Unroll dough into 2 long rectangles. Place in pan; press over bottom and 1/2 inch up sides to form crust.
Bake 5 minutes. Sprinkle chips and nuts evenly over crust. Pour sweetened condensed milk evenly over top.
Bake 20 to 25 minutes longer or until golden brown. Cool 10 minutes. Run knife around sides of pan to loosen. Cool 1 hour. Refrigerate 30 minutes or until chocolate is set. For bars, cut into 6 rows by 6 rows.