In a small bowl, combine flour, baking soda and salt; set aside.
In a large bowl, combine butter, sugar, brown sugar and vanilla extract. Beat until creamy. Beat in egg.
Gradually add flour mixture; mix well. Stir in chocolate chips and nuts.
Spread dough into a greased 9-inch square pan.
Bake at 375°F for 20-25 minutes. Cool.
Cut into about 16 2-inch squares.
Notes
For a crisper pan cookie: follow the same directions but spread dough into a greased 13 x 9 x 2-inch pan. Bake at 375°F for 12-15 minutes. Makes 24 2-inch squares.