In a large mixing bowl, combine peanut butter and oil. Add brown sugar and sugar and mix well. Add eggs and vanilla, mix well. Combine flour, cocoa, soda and salt. Add to the peanut butter mixture until blended. Stir in chocolate chips.
Drop by rounded teaspoonfuls 2 inches apart on ungreased cookie sheet. Flatten slightly with a glass. Bake at 350 for 8-10 minutes or until set and tops are cracked. Cool for 2 minutes before removing to wire rack.