Very seldom do good ideas come from a hangover—typically a state of discomfort reserved for moments of regret and greasy comfort food—but it’s exactly how the idea for Cereal Killer Cafe came to Alan and Gary Keery.

The identical twins from Belfast, Ireland are the creators behind London’s cereal-only establishment. That’s right: a place dedicated to cereal. “Me and my brother were in Shoreditch and we were hung over. We thought it would be nice just to go somewhere, sit down, and have a bowl of cereal,” says Alan, sitting in the back of the Camden Market location. “And then we realized that there was nowhere to get that in London, or the U.K., or Europe, so that’s when the light bulb moment happened.” That was three years ago.

Today, the two locations (the other being Brick Lane) each offer 120 varieties of cereal imported from all over the globe, with some nearly impossible to find anywhere else in the U.K.—there are brands from Spain, Israel, Australia, and France. Bowls can be served straight up with just one kind of cereal and regular milk for those wanting simplicity, or a “cocktail” can be crafted from one of the 30 different flavours of milk (everything from bubblegum to cinnamon) on offer. Up to three kinds of cereal can be mixed together, and toppings such as Oreos and bananas can be added.

The Camden spot is tucked away within the historic and eclectic market, where visitors can stock up on everything from produce to light-up rave attire. The interior is equally eclectic, with patrons sitting on single beds topped with cartoon character duvets and toys from cereal boxes tacked all over the walls. “We realized that if it was going to be a cereal cafe, we need to have cereals from all over the world, and we would need to decorate it with all the toys you used to get in cereal and all the great things from cereal boxes,” says Alan. “So it just kind of turned into a whole shrine to the ‘90s, really.” Vintage cartoons play on retro televisions within the space, truly setting the scene for a Saturday morning spent watching television and eating the most sugary cereal that mum agrees to.

Both cafes are kept busy with regulars and inquisitive tourists, but it hasn’t been all cheery childhood nostalgia for the burgeoning business. The Brick Lane location was the target of protests and vandalism by an anti-gentrification organization frustrated with changes in the blue-collar-turned-trendy neighbourhood; in September 2015, hundreds of protesters turned up to throw paint at the windows while brandishing flaming torches while customers were inside. “They targeted us just to get press—and they did get press—so well done to them, but I think a lot of people see what they did as misdirected anger,” Alan says. “They do have some valuable points to bring up, but they just went about it completely the wrong way.” He adds: “They said that we are figuratively burning £50 notes in the face of the poor because we are selling cereal at a markup, but I’m not too sure whether they understand exactly what businesses do.” Despite the push back, the brothers are continuing expand the enterprise, opening their first internationally licensed location in Dubai in May. Alan names New York City and Amsterdam as his dream cities to set up shop in.

The twins have also written a cookbook, released last year: Cereal Killer Cafe Cookbook centres on cooking with cereal, of course, and also offers up trivia and anecdotes. Alan credits their success to their deep sibling connection. “We have always fought quite a lot, but we live together, we work together, we socialize together, so it is a bit full-on,” he says. “But you know what? I couldn’t do this job with anybody else other than with Gary.” How very sweet.

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