I Learned How to Make Birthday Cake From the Masters at Milk Bar

The average Brooklyn warehouse isn’t filled with the heady, sweet aroma of freshly baked cakes and sprinkle-infused cookies — but this is no ordinary warehouse. Alongside Milk Bar’s Williamsburg storefront, where patrons filter in and out to get their fill of Cereal Milk-flavored soft serve and fluffy pork buns, is their production kitchen. Though this low-key space isn’t equipped with elaborate, Wonka-like candy trappings or a chocolate river (though that would make for quite the tour attraction), within still lies a world of sugary goodness.

Founded in 2008 by chef and owner Christina Tosi — Masterchef judge and all-around badass pastry boss — Milk Bar is the sister bakery of David Chang’s Momofuku restaurant group.

Having released two cookbooks, “Momofuku Milk Bar” and “Milk Bar Life,” Tosi’s creation has grown a devoted following with the help of their addictive signature sweets, from Compost Cookies made with potato chips, pretzels, chocolate chips, and oats, to their aptly named Crack Pie. However, perhaps no two items are so ubiquitously loved (or Instagrammed) as their birthday cake and birthday cake truffles.

Most Instagrammable cake ever? I think so.

Though Milk Bar has a variety of unique cake flavors — from apple pie to salted pretzel to dulce de leche — none is as famous as their Birthday Cake, with visible layers of colorful confetti cake, vanilla frosting, and crunchy cake “crumbles” sprinkled throughout.

The first time I encountered this cake, I was an intern at a major national food magazine and was sent across town to pick up and hand deliver a Milk Bar Birthday Cake for an office celebration — I had to be careful, I was told; this was precious cargo. What’s the BFD with this cake? I thought. One bite, and I knew — this was no mere mound of sugar and flour.

Naturally, when I found out Milk Bar offered a baking class to learn how to make your very own Birthday Cake as part of their Bake the Book series, I was pretty excited (okay, that’s an understatement). I instantly enlisted my most enthusiastically cake-loving friend, Rachel, and we booked a couple of spots.

When we arrived on Saturday morning, a sign was propped up on the doors to the warehouse asking us to wait outside — someone would come get us soon. I impatiently fanned myself with my Metrocard and thought about how dumb it was to have skipped breakfast before coming to a baking class, working hard to resist the siren call of the hot, pillowy pork buns in my near vicinity. 

Who could resist this pork-filled beaut?

Finally, our instructor came to fetch us. Upbeat, quirky, with hair tied up in a floral head wrap, she was exactly how you would expect a Milk Bar baker to be. “Oh my god, I want that head scarf,” Rachel whispered to me. Seconds later, we were told we’d be getting one of our own — major score.

But first came the hairnets. The instructor passed them around, promising they’d only have to remain on as we walked through the factory on the way to the classroom in the rear. We pulled the nets over our heads and I quickly determined that it probably wasn’t my best look.

Rachel and I, killin’ the hairnet game. 

The warehouse was bustling with people hand-crafting truffles, stirring large vats of frosting, and mixing batches of cookie dough in bowls approximately the size of my apartment.

Finally, it was time to learn how to make Birthday Cake. Our classroom was tucked away in the rear of the building, and there we found rows of pre-baked sheet cakes topped with a bevy of rainbow sprinkles. Since the class was only two hours long, to save time the cakes are pre-baked in sheets so we could get straight to the fun part—construction. (Rest assured, the easy-to-follow recipe is available in their cookbook and online.)

Baking round cakes in rectangular sheet pans is one of Milk Bar’s tricks of the trade. Rather than using a typical circular pan, which often results in an undercooked middle or overcooked edge, Milk Bar carves out circles from the sheets, guaranteeing a perfectly even bake and allowing for their signature layered look.

Our instructor dissing an average, circular cake pan. Sooo not Milk Bar’s style.

An added bonus to this method was that we got to eat all the of the cake that fell outside the boundaries of the circles. And when I say I ate all of the extra cake, I mean all of the extra cake.

To create the layered effect, there’s a specific formula — one we followed closely using 6-inch metal rings and plastic transfer sheets to hold everything together during construction. First comes a layer of cake, topped with a couple tablespoons of a milk and clear* vanilla extract mixture to keep it moist. Next, a layer of frosting, a sprinkle of “birthday cake crumbs,” and more frosting. Then, this process is repeated three times, concluding with a triumphant pile of crumbs at the top. (*Clear vanilla extract is Milk Bar’s key ingredient for nailing the distinctive Birthday Cake flavor.)

Our completed creations were swept away to cool for a few minutes as we got to work on making our own batch of Milk Bar’s famed B-Day Truffles and tried our hardest to not to experience separation anxiety from our cakes.

Pre-truffle (and pre-my stomach) sheet cakes. 

The truffles were created as a solution to the excess cake they had laying around after carving out their circular layers. (You mean to tell me they didn’t want to eat all of the extras themselves?? Crazy, I know.) In addition to being delicious, the truffles are also ridiculously easy to make. Simply take your extra cake — any cake — add a little bit of milk, and mix until it’s moist enough to be rolled into balls. To coat the balls, roll them lightly in white chocolate melted with a little cooking oil to give it a creamy texture. Then roll the truffles in a crunchy outer coating of your choosing. The birthday cake truffles are coated in ground-up birthday crumbles, but ground cookies, nuts, etc., could also be used.

At the end of the class, our cakes were returned to us, unveiled from their metal rings, and we felt like proud parents picking our kids up at the end of the first day of school. They were glorious. Though Rachel’s was decidedly prettier than mine — she’s kind of a baking prodigy — I was proud of my creation, and couldn’t wait to take it home.

Despite being stuffed to the brim with cake, I couldn’t resist grabbing a pork bun before hopping on the subway, cradling my cake in my arms like an infant the whole way home.

Once home, knowing how dangerous it was to have an entire cake hanging out in my fridge all weekend (I have an embarrassingly low level of self control and a rampant sweet tooth), I promptly texted my friends and roommates demanding they come eat some. But not before posing for a few #cakeselfies first, obviously.

First, let me take a selfie.

The best part is, now armed with the magical Milk Bar cake-making secrets, I’m well prepared to repeat the process again and again with all kinds of layers and flavors. Maybe I’ll even go savory — a stuffing and mashed potato cake for Thanksgiving? I’m thinking hell yeah.

Now I’m itching to head back to another class soon. And with twice weekly classes offered for other Milk Bar favorites, like Crack Pie and Chocolate Malt Cake, I’m sure I won’t stay away for long.

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