toffee cookie squares

from Carolyn Smith
Makes 3 dozen bars
½ cup butter or margarine
½ cup shortening
1 cup brown sugar, firmly packed
1 egg yolk, unbeaten
1 tsp vanilla
½ tsp salt
2 cups sifted flour
1 6oz package semi sweet chocolate chips
½ cup chopped nuts

Cream together butter, shortening, sugar and egg yolk. Stir in vanilla, salt and flour. Pat mixture into 15 ½ x 10 ½ x 1” pan. Bake slow in oven 325 degrees 15 to 20 minutes. Melt chocolate; spread over warm baked mixture. Sprinkle with chopped nuts. Cut into squares.