The Truth About Costco Sheet Cakes

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People flock to Costco for many reasons. For some, it's all about the bulk toilet paper, per CNBC. For others, it's the love of seemingly inflation-proof rotisserie chicken. For others still — particularly in the case of parental units and others in the position of having to plan multiple birthday parties each year — it's Costco's sheet cake that has them ponying up the retailer's annual membership fee, year after year after year. 

Fortunately for lovers of buttercream frosted layer cakes that are sized to feed a small army (or at least a classroom or two of hungry middle-schoolers), rumors of the Costco sheet cake's demise have turned out to be greatly exaggerated (albeit oddly persistent), according to Cheapism. And so it is that Costco sheet cakes are still available as a perk for Costco members (and only Costco members, because Costco cakes can only be purchased in-store, as Costco spells out on its website). It's not a free perk like Costco's famous and abundant samples, but Costco's sheet cake is seen by many as a good value, nevertheless. 

Consisting of two 12" x 16" layers of cake separated by a fluffy creamy mousse, slathered in real buttercream frosting, and customizable to order, Costco's sheet cake is, technically speaking, a half sheet cake, according to Web Restaurant Store. And that's the first of many sweet facts about Costco's sheet cakes that only savvy shoppers such as yourself will now know. 

Easily customizable and available in a pinch, the options are endless when it comes to Costco's signature half-sheet cakes — except in terms of taste. The confections are only available in two different flavors: white cake layered with vanilla cheesecake mousse (a whole two pounds of it!) and topped with decadent vanilla buttercream frosting, or chocolate cake filled with chocolate mousse and, you guessed it, iced with chocolate buttercream. Not exactly a lot of variety, but they get the job done. 

Meanwhile, the warehouse store's bakery offers other sweet treats, such as a mini carrot cake with cream cheese frosting and (to some folks' chagrin) raisins. Equally impressive is the flavor bonus offered by Costco's Australian stores: Shoppers have the option of adding raspberry or chocolate filling to compliment either the chocolate or vanilla sponge cake. Given the dessert's enduring popularity, though, American customers clearly appreciate each cake's quality and freshness, and don't mind a more tailored approach to these treats.

Between its size, taste and price, the retailer's most-loved dessert might just be the ultimate budget bite. Costco's trademark treat is a steal at $24.99 (per Aisle of Shame), especially considering their ability to be customized to any style or occasion. The cost for a cake from a high-end independent patisserie can easily eek up into the triple digits, and even a confection from your run-of-the-mill local bakery still costs a few dollars more than the reliable Costco standby (via Know More Stuff). 

According to one Facebook commenter, the taste of the cake rivals a fancy bakery as well: "I've been marketing that cake to everyone for several years. Also served it at my daughter's wedding in fear the big wedding cake wasn't enough. I got more compliments on the Costco cake than the $400 cake!" Low cost aside, the time you save not slaving away over a bowl of batter before your birthday bash is priceless.

Sheet cakes are perfect for parties, but there's no rule saying you can't buy one for yourself with the intention of enjoying a slice every day while still fresh. The question is, how long can a Costco sheet cake stay fresh? The answer depends on where and how you're storing it.

First things first, it doesn't seem like a great idea to store any sweet and moist baked good at room temperature, per Baking Business. Although baked goods aren't particularly vulnerable to microbial contamination, they will spoil more quickly if left unrefrigerated. They'll also lose moisture rapidly outside the fridge, per Query Sprout. According to Cake Re, a refrigerated cake with buttercream frosting will last anywhere from three to four days, and slightly less if filled with a creamy mousse like Costco's sheet cakes are. 

On the other hand, some Redditors on the Costco subreddit suggest Costco cakes may stay fresh in the fridge for up to a week or slightly longer. Moreover, if you freeze your sheet cake, you may still be able to enjoy it three months from now, or even longer if you carefully wrap each individual slice, per The New York Times. But if you're buying a Costco sheet cake for a party, then you're probably best off doing so as close to the event as possible. Store it unopened in the fridge, transferring it to room temperature about no more than an hour before serving (via Southern Living).

Back in 2015, a Costco controversy broke out due to a mother complaining that her son's dinosaur-themed birthday cake contained Satanic symbolism. According to an article by the Inquisitr (via Snopes), the woman purchased the cake in question at the Superstition Springs Costco location in Mesa, AZ, likely drawn to the friendly-looking blue and green dinosaur prancing through grass drawn in icing across the surface. As she was singing "Happy Birthday" to her son, however, she noticed that the dino's three visible legs seemed to be in the shape of "666," a numerical sequence commonly associated with the devil.

"I was extremely shocked and upset to see a demonic symbol written clear as day on my 6-year-old son's birthday cake," says the woman. "What was supposed to be a whimsical dinosaur became something very distasteful. I was extremely surprised at Costco for allowing such an inappropriate joke be sold to an unsuspecting victim." Although the claims have been debunked since and thought to be orchestrated by the woman and her boyfriend (a reporter), there were exactly 666 Costco stores spread across the world at the time of the scandal. Oooh, spooky!

To the dismay of all cake enthusiasts, Costco released a Facebook advertisement in late May 2020 encouraging members to purchase cakes to celebrate graduations — only the cakes pictured in the ad were the bakery's 10-inch round cake, not the fan-favorite half-sheet cake. At the bottom of the post, it broke the upsetting news: "Please note: Half-sheet cakes are currently not available to order or customize." Weeks later, the warehouse retailer confirmed in a statement to Business Insider that they had no intention of restocking the cakes. 

According to The New York Times, the loss of the sheet cakes could be attributed to the coronavirus pandemic, where gatherings for larger groups have gone by the wayside along with hugs and handshakes. "To help limit personal contact and create more space for social distancing, Costco has reduced service in some departments," the retailer explained. "At this time, we are not making sheet cakes for special order." 

Although Costco originally claimed that the 10-inch round cakes "[seemed] to be resonating" with members" (per Business Insider), a Change.org petition was formed not too long after the store announced that they would be discontinuing the beloved dessert. It racked up over 1,500 signatures, with many signers expressing their adoration in the "reasons for signing" section. 

Fortunately, Costco brought the fan-favorite cake back less than two years later, albeit at a slightly higher price than its original $19 price tag (via Cheapism).

So, you know how we just told you that if you forgot to order your half sheet cake in advance from Sam's Club, you can nevertheless still buy one through the Sam's Club bakery — it just won't be frosted or custom-decorated, and it will cost a few dollars more? Well, the same is generally true with regard to the half sheet cakes at Costco, except that your Costco ready-to-take-home sheet cake will come frosted — albeit not decorated — and it won't cost you a penny more. 

Obviously, if you happen to be creatively inclined, then this could be a really fun opportunity for you. Just look at all the fun the person who hand-decorated the above Costco sheet cake apparently got to have! Seriously, who amongst us has not fantasized (and during our adult years, no less) of squeezing a personally curated selection of sweet and colorful frostings all over a blank slate of a frosted sheet cake? Well, if you haven't, it could be an idea worth considering, especially if you're one of those people who likes to be prepared for anything. Because if that's your jam, then you could conceivably stock your storage freezer with a couple of extra Costco sheet cakes and the various accoutrements you need for cake decorating, for the purpose of having them on hand for those times when friends and family descend without warning. 

There's no doubt that many regard the Costco sheet cake as a sweet and gooey gift from the supermarket gods. But perhaps you're an amateur baker who dreams of perhaps making and decorating your own half sheet cake from scratch. If so, you're in luck, because one of our recipe developers here at Mashed has managed to reverse engineer the classic vanilla Costco sheet cake, with great success. Now, you too can make it at home. 

Our recipe for copycat vanilla Costco sheet cake requires a mere 45 minutes of prep time and 20 minutes of baking time, and it will yield you around 20 servings. It's rated, on average, five out of five stars by more than 600 of our readers, so clearly, it won't steer you wrong. But there is one caveat, which is that it requires a shopping trip's worth of ingredients: white sugar, flour, baking powder, baking soda, salt, milk, eggs, vegetable oil, and vanilla extract for the cake, heavy cream, milk, and instant pudding mix for the filling, and powdered sugar, sweet butter, and vanilla extract for the buttercream frosting. 

By our estimates, if you have to buy all of those ingredients new from the supermarket, then this cake will set you back roughly $50 to $60. Assuming you have some of these ingredients already in your kitchen, then you might say, that's the icing on the cake.