Pop-Tarts, a popular toaster pastry, were introduced by Kellogg's in 1964, revolutionizing the breakfast food market with their convenience and sweet appeal. Initially created as a way to compete with Post's unreleased "Country Squares," Pop-Tarts were originally unfrosted due to concerns about frosting surviving the toaster. However, frosted versions quickly followed due to popular demand. The first flavors included Strawberry, Blueberry, Brown Sugar Cinnamon, and Apple-Currant, with the latter soon replaced by Apple. Pop-Tarts became a cultural phenomenon, expanding into a wide variety of flavors and even limited-edition runs, capturing the imagination and taste buds of multiple generations.