Who says breakfast has to be boring? With a pint of your favorite ice-cream, Girl Scout Do-si-dos cookies, peanut butter, and cereal, you can have a deliciously fun and filling breakfast shake! Try our Peanut Butter Breakfast Cereal Cookie Milkshake- get the recipe down below!  Peanut Butter Breakfast Cereal Cookie Milkshake MmmKay. Here we go.