Even some McDonald's employees don't know about this fast-food chain's unique and cheap birthday cake. However, please leave it to TikTokers to reveal all the hidden treasures since they are the PI's for the Internet era.

Here's what you need to know about the McDonald's birthday cake that went viral overnight!

The birth of the cake

TikTok user kayrock93 uploaded a video of her visit to the local McDonald's. It sounds like any other TikTok video, but when people saw the cake, things got wild.

McCake is available in your chocolate or vanilla choice, covered in vanilla frosting, and features Ronald McDonald's image. It looks McDelicious!

With the price of just 9 bucks, it's great for any celebration, from getting up on Mondays to office parties. However, there's a catch, which might make you regret you even learned about this hidden McDonald's treasure.

You can't get it everywhere

Yes, sadly, the newly beloved McCake, as we decided to call it, is not available in every restaurant.

There's only one way to know whether your local McDonald's has it, so get up, dress up, and hit the famous fast-food chain.

Now, some employees will be confused, because they never heard of it, but you can show them this article, and they can do you one more: ask their coworkers where's the nearest location with your cake.

One of the best-kept McDonald's secrets is out, and we're not settling until we try a piece of this sheet cake!

P.S. We really love these hidden menus, so keep digging TikTokers!