In a bowl, sift flour, cocoa, cinnamon, and baking soda, and salt.
Beat together butter, brown sugar, sugar with an electric mixer on medium to high speed. Add eggs, one at a time, beating until combined. Beat in vanilla Add flour mixture, mix well. Stir in chocolate chips.
Drop by rounded tablespoonfuls about 2 inches apart on an ungreased cookie sheet. Bake 9 minutes or until edges are firm and center are soft. Transfer to wire rack to cool.