Cereal Killer Café in London is a cereal lover's dream. "At Cereal Killer Café, we don't just sell a bowl of cereal. We sell cereal in every way imaginable," owner Alan Keery Told Business Insider.

Breakfast sandwiches have become a "cereal killer" because they're a portable, convenient source of protein that can be eaten on the run — no bowl required, The Washington Post reported.