Combine chopped dates, boiling water, and soda. Stir, and allow to cool.
Whisk together flour, baking powder, and nuts.
In a large mixing bowl, beat together egg, salt, sugar, and vanilla. Blend together melted chocolate and melted butter or margarine; stir into batter. Stir in date mixture. Add flour mixture, and stir to mix. Scrape into a greased 9 x 5 inch loaf pan.
Bake at 350 degrees F (175 degrees C) for 1 hour, or until it tests done. Cool in pan 10 minutes. Remove from pan.