1. Heat oven to 350°F.
2. Beat butter, sugar, eggs and vanilla in large bowl until light and fluffy. Stir together flour, cocoa, baking soda and salt; add to butter mixture, beating until well blended. Stir in chocolates and nuts, if desired. Drop by tablespoonfuls onto ungreased cookie sheet.
3. Bake 8 to 10 minutes or just until set. Cool slightly; remove from cookie sheet to wire rack. Cool completely. Makes about 42 cookies.