Source: The Jewish Celebrity Cookbook

1 cup (2 sticks) butter, room temperature
1 cup packed brown sugar
1 egg yolk
1 cup flour
9 1/4 ounces semisweet or milk chocolate candy bars
      (six 1.55 oz, bars), broken up, or 1 rounded cup chocolate chips
2/3 cup chopped pecans

Preheat oven to 350 degrees F. Line a 15 x 10-inch jellyroll pan with foil. Grease foil.

In bowl, cream butter and sugar until fluffy. Add egg yolk and mix well. Add flour and stir until mixed.

Spread dough in prepared pan. Bake in preheated oven for 20 minutes or until browned.

Remove from oven and immediately top with chocolate. When chocolate has melted, spread with spatula. Top with pecans.

Cool slightly, then cut on the diagonal into diamond shapes. When completely cool, recut. Makes several dozen pieces, depending on size.