Oreo cookies come in just about every flavor. From waffles and syrup to cookie butter to Swedish Fish, the Wonder Vault is anything but short on ideas for re-imagining everyone’s favorite sandwich cookie (sorry, Hydrox). So when an Instagram account leaked word that there would be a Mystery Oreo coming out this year, it begged the question: What flavors haven’t been done?
The Mystery Oreos arrived at the Food & Wine offices on Friday in a locked, white box emblazoned with a cookie-dotted question mark on the top. Once we bested the lock, the box appeared empty until further investigation revealed a side panel that was concealing the hidden, all-white package of Oreos.
Upon opening the package, we were immediately hit with a waft of artificial fruit flavor. The cookies, however, look no different than the traditional black and white Oreos we’re used to seeing, though they do appear to be double stuffed. The wafers themselves are chocolate-flavored, but it’s the creme that gives off the distinct aroma we first encountered. So, we asked the Food & Wine staff to write down their best guesses as to what the mysterious flavor could be and the results were almost unanimously “Fruity Pebbles.” Yes, we’re talking the Flintstones-themed breakfast cereal. Given that Oreo has teamed up with brands like Dunkin’ Donuts and Peeps before, it’s certainly possible. But Oreo did already release a “Fruity Crisp” flavor once before with golden cookies on the the outside, so it would seem odd for the Mystery Oreos to be a reboot of an existing cookie.
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When the sweet filling is eaten with the chocolate wafers, another thought crossed our mind. One person suggested the cookies could be Cocoa Puffs-flavored, putting the entire cookie squarely in the cereal aisle. To that end, perhaps our most encompassing guess, given the fruity filling and chocolate cookies, is “Cereal Milk Oreos,” akin to the steeped, sugary beverage Christina Tosi made famous at Momofuku Milk Bar. As far as reactions to the flavor, they were mixed with some people going back for seconds and others saying one was enough.
Once you get your hands on the Mystery Oreos, you can take a shot and guessing the flavor on the Mystery Oreo website for a chance to win $50,000. According to the site, we are trying to guess the mystery creme flavor itself, so take that into consideration. So if you do indeed submit “Cereal Milk” as your own and are indeed correct, and you do indeed win the grand prize, all we ask is that you buy us a pack of Oreos and a bottle of milk. It’s the least you can do!
This article originally appeared on Foodandwine.com