Preheat oven to 350 degrees. Lightly grease a 13-inch by 9-inch baking pan.
Cream butter, sugar, egg yolk, and vanilla until light and fluffy. Stir in flour and salt; blend well. Pat over bottom of prepared pan. Bake 20 to 25 minutes, until golden brown.
Remove bars from oven; distribute chocolate chips evenly over top. Let stand 5 minutes to melt; spread evenly. Sprinkle with nuts. Cut while warm.
Makes 24Recipe submitted by Joyce on 11/7/00