Preheat oven to 350 degrees. Place dates in small bowl. Sprinkle with baking soda; add hot water. Let stand 5 to 10 minutes to plump dates. In large mixing bowl, cream sugar and butter or margarine together. Add eggs. Beat well again. Sift flour, salt and cocoa together. Add dry ingredients to sugar-butter mixture in small amounts, alternating with date mixture. Add vanilla and mix well. Fold in half cup of chocolate chips. Pour into greased and floured 9 x 13 x 5 cm baking pan. Sprinkle remaining chocolate chips and chopped nuts over top. Bake 40 to 45 minutes or until toothpick inserted in center comes out clean.