Heat oven to 350°F. Grease 15x10x1-inch pan. In large bowl, beat brown sugar and butter with electric mixer on medium speed until light and fluffy. Beat in molasses, vanilla and eggs. Stir in oats, flour, baking soda and salt. Stir in nuts and chocolate chips. Spread in pan.
Bake 20 to 30 minutes or until light golden brown and center is set. Cool completely, about 1 hour. For bars, cut into 8 rows by 6 rows.