1. Mix the sugar and cocoa.
2. Whip the egg white and salt until stiff; gradually add the cocoa mixture to the egg white, beating thoroughly after each addition; then continue beating 2 or 3 minutes longer. Fold in the nuts.
3. Pile the mixture over cake batter in a shallow baking pan; or spread over cupcake or muffin pans filled with batter.
4. Bake in a Moderate, 350° F., oven 20 to 25 minutes. Enough meringue for an 8-inch square cake, or 8 to 12 cupcakes.