Cream margarine and sugar in large bowl with mixer. Add eggs and vanilla; Blendwell. Combine flour, cocoa, baking soda and salt; blend into creamed mixture. Stir in nuts. Drop by teaspoonfuls onto ungreased baking sheet. Bake at 350° for 8 to 10 minutes. Do not overbake. Cookies will be soft. They will puff during baking, flatten upon cooling. Cool on baking sheet about one minute or until set; remove to wire rack to cool completely. This recipe makes 4 1/2 dozen.