1/2 c. butter, softened
1/4 c. sugar
1/4 c. brown sugar
1/2 tsp. vanilla
1 egg
1 c. flour
1/2 tsp. baking soda
1/2 tsp. salt
1 (6 oz.) pkg. chocolate chips
1/2 c. walnuts (optional)

Heat oven to 375 degrees. Grease 9 x 9 x 2-inch pan. Mix butter, sugar and vanilla. Beat in egg. Blend in flour, baking soda and salt. Add walnuts. Spread in prepared pan. Sprinkle chocolate chips over top. Place in oven 2 minutes. Remove from oven and run knife through dough to marbelize. Return to oven and bake 12 to 14 minutes. Cool, cut and enjoy.