3 sticks butter
1 box brown sugar
2 egg yolks, beaten with fork
4 c. flour
1 tsp. baking soda
1 tsp. vanilla

Melt the 3 sticks of butter and brown sugar together. Add other ingredients and mix well. Pour into a large greased cookie sheet with sides, and bake for 20 minutes at 375. Ice while hot.

ICING:

3 c. powdered sugar
2 egg whites, unbeaten
4 tbsp. cocoa
1/2 stick butter, softened
1/2 tsp. vanilla

Mix all ingredients well and spread over hot toffee bars. Cut in squares.