Beat egg whites (at room temperature) in a medium mixing bowl until stiff peaks form. Gradually sift sugar, cocoa, and salt over surface of egg whites; gently fold into egg whites. Fold in pecans.
Drop by heaping teaspoonfuls 1 inch apart onto well-greased cookie sheets. Bake at 300° for 35 minutes. Cool slightly on cookie sheets. Gently remove from cookie sheets, and cool completely on wire racks. Store in an airtight container.