//In medium bowl, stir together Krusteaz Butter Vanilla Sugar Cookie Mix, butter and egg until well blended. Divide dough in half. Add cocoa powder to one half of dough. Hand knead to incorporate cocoa. On lightly floured surface, roll dough into two separate 12-inch logs.
//Chill dough logs 30 minutes. Place chilled logs side by side and roll together into 20-inch log. Fold log in half and place side by side, alternating colors. Roll dough to 12-inch log; twist log several times to marble the dough. Chill 15 minutes.
//Slice dough into 1/4-inch slices and place 2 inches apart onto ungreased cookie sheet.