Colby-Jack, or Cojack, is a cheese produced from a mixture of Colby and Monterey Jack cheeses. It is generally sold in a full-moon or a half-moon shape when it. Colby Jack Cheese. A Classic North American Cheese that blends Colby and Monterey Jack Cheese together for a colorful semi soft cheese with a clean mild. A semi-soft cheese, it exhibits a unique eye-appealing marbled white and orange The taste of Colby Jack varies from mild and smooth, to lightly sweet.