In large bowl, beat butter, granulated sugar, brown sugar and vanilla on medium speed of electric mixer about 2 minutes or until creamy.
Add eggs; beat well.
Stir together flour, cocoa, baking soda, baking powder and salt; gradually add to butter mixture, beating just until blended. Stir in chocolate chips and nuts. Drop by heaping teaspoonfuls onto ungreased cookie sheet.
Bake 7 minutes or until set. Cool 1 minute; remove from cookie sheet to wire rack. Cool completely.