Preheat oven to 300 degrees F (150 degrees C). Line 2 baking sheets with parchment paper. Sift 1/4 cup sugar, cocoa, and salt into a small bowl.
In a large bowl, beat egg whites with an electric mixer until soft peaks begin to form. Mix in remaining 1/4 cup of sugar gradually, and beat until medium-firm peaks form. Sprinkle in cocoa mixture gradually, and continue beating until egg whites are stiff. Fold in chocolate chips. Drop mixture onto baking sheets by rounded teaspoonfuls, spacing about 1 inch apart.
Bake in preheated oven for 40 minutes for crispy cookies. Cool cookies on baking sheets.
