Use one 10 1/2 by 15 1/2-inch jelly roll pan, buttered and lined with parchment Or wax paper.

Cut chocolate and butter into 1-inch pieces and place in a dry bowl or the top of a double boiler. Set over a pan of hot water and stir occasionally until melted. Meanwhile, combine eggs with sugars, vanilla and salt and whip on medium speed until light. Stir in chocolate mixture and sift over and fold in flour. Stir in nuts. Spread batter in pan and scatter more chopped nuts on surface, if desired. Bake at 375 degrees about 40 minutes until firm, but still moist. Cool in pan on rack. Cut into 2-inch squares to serve.

Serving: Serve as cookies, of course, or cut the brownies into 3-inch squares and serve topped with ice cream for a lavishly rich dessert.

Storage: Keep the brownies tightly wrapped at room temperature or wrap in a single layer and freeze.