Find the Chocolate Birthday Cake Shake and Cornflake Chocolate Drizzle Shake at stores all month long!

You'll want to blow out the candles and make a wish when you see Shake Shack's latest collaboration. The fast-food chain just released two milkshakes with bakery Milk Bar that are available to order now.

It's not surprising Shake Shack and Milk Bar would join forces at some point, considering both are based in New York City and specialize in deliciously nostalgic eats that take us back to our childhood. And these treats, in particular, are the stuff birthday dreams are made of.

The Chocolate Birthday Cake Shake features the bakery's signature B'Day cake crumbs and frosting blended in a chocolate cake custard, with whipped cream and sprinkles on top. The Cornflake Chocolate Drizzle Shake combines malted vanilla custard and Milk Bar's Cornflake Crunch, with a drizzle of chocolate sauce and mini marshmallows to finish it off. In other words, salty-sweet perfection.

Milk Bar opened in 2008 under the helm of chef Christina Tosi, who previously worked at the trendy Manhattan eatery Momofuku. After testing out her desserts at the restaurant, she eventually opened her own storefront in New York's East Village and gained a word-of-mouth reputation for unexpected sweets like Cereal Milk and the Compost Cookie. In addition to nine stores in New York, Milk Bar has since expanded with locations in Los Angeles, Toronto, and D.C.

To sweeten things further, Shake Shack is also surprising fans with free milkshakes. Just visit their Instagram every Friday this month for a random drawing of calendar dates. If your birthday is chosen, you can message them and get a code for a free shake. Codes can be redeemed on their app and will be given to the first 50 people who respond, so you'll want to be quick!

The shakes dropped on September 3, but they'll be around for sipping all month long. So treat yourself like the birthday boy or girl you are and head over to your nearest Shack to try them—no invite necessary. You deserve it!

What do you think of this collaboration? Are there any businesses you'd like to see Shake Shack team up with in the future? Sound off in the comments.