Cap'n Crunch's Peanut Butter Crunch Cereal. Indulge in the Irresistible Taste of Peanut Butter. Each bowlful of Cap'n Crunch's Peanut Butter Crunch is filled with the rich peanut butter flavor and unmistakable CRUNCH you've loved since childhood. It's fortified with seven essential vitamins and minerals and has zero grams of trans fat. Just add low-fat milk and a glass of 100% juice for a low-fat, balanced breakfast.