1 c. butter (1/2 butter)
1 c. brown sugar
1 egg yolk
1 tsp. vanilla
2 c. flour

Mix. Pour into 10x15 inch pan (cookie sheet with edges). Bake 20 minutes, 350 degree oven.

Place 6 Hershey milk chocolate bars on top at once. When melted spread evenly. Top with ground nuts if desired. Cut in squares at once.