Toasted Maize Cereal and Milk Bar. Too good to go. Past my date?. Look, Smell, Taste. Kellogg's Frosties cereal are the perfect way to take the grrrreat taste of a bowl of Frosties with you anywhere you go. Our Kellogg's Frosties cereal breakfast bar combines Frosties' crunch with a milky layer. The bar is a source of calcium and vitamin D. Kellogg's Frosties cereal breakfast bars are great for a tasty mid-morning snack or something on-the-go. Each bar is a source of fibre, calcium, and vitamin D