Modified from Great
1 lb (2 1/4 cups) brown sugar
1 cup butter
2 eggs
2 cups flour
1 tsp baking powder
1/2 tsp salt
1 cup walnuts
Cook sugar and butter in top of a double boiler (which I don't have, so I just nest two pots to create one) until sugar is dissolved. Cool.
Add eggs one at a time and beat thoroughly after each. Then stir in rest of ingredients and spread into an ungreased sheet pan (really a sheet pan, like 15.5 by 11.5 by 0.5 which is what was written, mine was slightly off those measurements).
Bake at 350 for 25 minutes (which I think was a little long). While hot, cut into small squares.