1. Heat oven to 350 degrees F. Lightly grease 2 baking sheets. Mix together flour, baking soda and salt in a bowl.
2. Beat brown sugar and butter in bowl until creamy and smooth, about 2 minutes. Beat in egg and vanilla. Stir in flour mixture. Fold in nuts and chocolate pieces. Drop by rounded measuring tablespoonfuls, 2 inches apart, onto prepared baking sheets.
3. Bake in 350 degrees F oven 10 to 12 minutes or until lightly browned at edges. Let cool slightly on baking sheets. Transfer to wire rack to cool. Store in airtight container.