Congo Bars

I was talking with my brother Stephan, and he mentioned this incredible sandwich that he makes. It is freshly sliced peaches with fresh spinach and sliced red onion, topped with Grey Poupon. Actually, I think most of his dishes require Grey Poupon!
Not quite ready to indulge that particular sandwich, I was reminded of the Congo Bars I would make and send to him at college, decades ago. The bars are still appreciated.

Preheat oven to 350F.

Congo Bars

2/3 cup butter, melted
2 cups dark brown sugar
3 eggs
2 3/4 cups flour
2 1/2 teaspoons baking powder
1/2 teaspoon salt
12 ounces semi-sweet chocolate morsels
1 cup walnuts or pecans, chopped
1 teaspoon vanilla

In a mixing bowl, combine butter and sugar.
Add eggs one at a time and beat well.
In a separate bowl blend flour, baking powder, and salt.
Add dry mixture to butter mixture.
Stir in chocolate, nuts, and vanilla.
Put into greased 9x13 inch baking pan.
Bake for 25-30 minutes, do not over bake.
Cut while warm.