Milk Bar Mondays: Chocolate Chip Layer Cake

I don’t think of myself as a celebrity stalker. I’ve never collected autographs. I don’t show up at premiers and scream. And I’ve never hid out in somebody’s car, hoping for a chance to introduce myself.

OK, maybe I did that just once to A. But he’s not a celebrity and things like that stop counting after 10 years. Right? Riiiiiiight.

But when somebody makes something or has an idea that I admire, I think it’s cool to tell them. “Hey, I think you’re smart.” “Hey, I think you’re cool.” “Hey, I like the way your brain works.” It’s the right thing to do.

You may have been reading about my adventures, along with a group of lovely friends, as we bake our way through this book.

There’s been butter. There’s been sugar. There’s been lots and lots of deliciousness and fun.

So when I had the chance to spend an afternoon with none other than the author of the book du jour, you best believe I snatched it.

So this is the story of a class, a cake and an afternoon with Christina Tosi. It’s bananas without the peel.

This is the cake that we made – Milk Bar’s Chocolate Chip Cake. It’s layered, it’s got chocolate, it’s got coffee-flavored frosting, and it’s laced with passion fruit juice. Shut. The front. Door.

We started the afternoon by watching Christina make the key elements that comprise the cake:  the cake layers itself, the frosting, the chocolate crumb and a passion fruit curd. As with everything else served at Milk Bar, the finished product is designed to evoke the classic, unfussy American desserts that you may remember from your childhood. We actually spent a lot of time talking about box cake mixes – pâte brisée, choux pastry and phyllo were MIA.

Next we had a chance to assemble our own cakes. I felt like a true Milkbarian! The book says that this cake was first made as a birthday cake for David Chang. Dang! That guy is lucky.

Assembly isn’t difficult. Especially if you, uh, have some willpower. If you don’t, that’s cool. Just prepare for a slightly smaller cake.

I asked Christina where she came up with the idea for this unique method of assembly. She had explained earlier in the day that Milk Bar bakes their cakes in quarter sheet pans in order to produce an evenly baked cake. They then stamp the rounds out with cake rings and assemble using the same ring as a base. Acetate strips act as building blocks that allow you to go vertical. The whole idea is to build a beautifully imperfect, perfect cake with sides that showcase all the hard work that you put into each layer. I can dig it.

Our cakes were finished in no time. You should know that you do need to chill your little gem before you peel off the acetate – the book recommends a minimum of 12 hours. Chilling insures that your acetate strips come off clean and your cake remains lovely.

The whole process takes a little work, but so do all extremely good things. Which is basically the theme of Milk Bar.

I love my little cake. He’s still in the freezer, waiting to be eaten. He doesn’t have much longer to wait.

And, really. What are you waiting for? You no longer have any excuses:  I’m including the recipe below. Do yourself a favor and make a Chocolate Chip Cake today.

P.S. While you’re baking, please take a moment to check out my Milk Bar Monday friends!:

Audra from The Baker Chick
Cassie from Bake Your Day
Erin from Big Fat Baker
Jacqueline from The Dusty Baker
Krissy from Krissy’s Creations
Nicole from Sweet Peony

Chocolate Chip Layer Cake

recipe from Momofuku Milk Bar

For the chocolate chip layer cake:
1 recipe chocolate chip cake (recipe follows)
1⁄3 c. passion fruit puree
1 recipe passion fruit curd (recipe follows)
1/2 recipe chocolate crumb (recipe follows)
1 recipe coffee frosting (recipe follows)
1/4 c. mini chocolate chips

For the chocolate chip cake:
8 tbsp. unsalted butter, softened
1 1/4 c. white sugar, granulated
1/4 c. light brown sugar, tightly packed
3 large eggs
1/2 c. buttermilk
1/2 c. grapeseed oil
1 tbsp. vanilla extract
1 1/2 cups cake flour
1 tsp. baking powder
1 tsp. kosher salt
Nonstick cooking spray (optional)
3/4 c. mini chocolate chips

For the passion fruit curd:
1/2 c. passion fruit puree
1⁄3 c. white sugar, granulated
2 large eggs
1 gelatin sheet
12 tbsp. unsalted butter, chilled
1/2 tsp. kosher salt

For the chocolate crumb:
2⁄3 c. all-purpose flour
1 tsp. cornstarch
1/2 c. white sugar, granulated
2⁄3 c. cocoa powder, preferably Valrhona
1 tsp. kosher salt
6 tbsp. unsalted butter, melted

For the coffee frosting:
8 tbsp. unsalted butter, softened
1/4 c. confectioners’ sugar
1/4 c. whole milk
3/4 tsp. instant coffee powder
1/4 tsp. kosher salt

Special equipment:
1 (6-inch) cake ring
2 strips acetate, each 3 inches wide and 20 inches long

To make the chocolate chip cake, preheat the oven to 350°.

Combine the butter and sugars in the bowl of a stand mixer fitted with the paddle attachment and cream together on medium-high for 2-3 minutes. Scrape down the sides of the bowl, add the eggs, and mix on medium-high again for 2-3 minutes. Scrape down the sides of the bowl once more. On low speed, stream in the buttermilk, oil, and vanilla. Increase the mixer speed to medium-high and paddle for 4-6 minutes, until the mixture is practically white, twice the size of your original fluffy butter-and-sugar mixture, and completely homogenous. Don’t rush the process. You’re basically forcing too much liquid into an already fatty mixture that doesn’t want to make room for the liquid. Stop the mixer and scrape down the sides of the bowl.

On very low speed, add the cake flour, baking powder, and salt. Mix for 45-60 seconds, just until your batter comes together and any remnants of dry ingredients have been incorporated. Scrape down the sides of the bowl. If you see any lumps of cake flour in there while you’re scraping, mix for another 45 seconds.

Spray a quarter sheet pan with cooking spray and line it with parchment, or just line the pan with a Silpat. Using a spatula, spread the cake batter in an even layer in the pan. Give the bottom of your sheet pan a tap on the countertop to even out the layer. Sprinkle the chocolate chips evenly over the cake batter. Bake the cake for 30-35 minutes. The cake will rise and puff, doubling in size, but will remain slightly buttery and dense. At 30 minutes, gently poke the edge of the cake with your finger:  the cake should bounce back slightly and the center should no longer be jiggly. Leave the cake in the oven for an extra 3-5 minutes if it doesn’t pass these tests.

Take the cake out of the oven and cool on a wire rack or, in a pinch, in the fridge or freezer (don’t worry, it’s not cheating). The cooled cake can be stored in the fridge, wrapped in plastic wrap, for up to 5 days.

To make the passion fruit curd, put the passion fruit puree and sugar in a blender and blend until the sugar granules have dissolved. Add the eggs and blend on low until you have a bright-orange-yellow mixture. Transfer the contents of the blender to a medium pot or saucepan. Clean the blender canister.

Bloom the gelatin (see below).

Heat the passion fruit mixture over low heat, whisking regularly. As it heats up, it will begin to thicken; keep a close eye on it. Once it boils, remove it from the stove and transfer it to the blender. Add the bloomed gelatin, butter, and salt and blend until the mixture is thick, shiny, and super-smooth. Transfer the mixture to a heatproof container, and put in the fridge until the curd has cooled completely, at least 30 minutes. The curd can be refrigerated for up to 1 week; do not freeze.

Tip:  Powdered gelatin can be substituted for the gelatin sheets:  use 1/2 teaspoon.

In order to incorporate it seamlessly into a mixture, gelatin must be softened, or “bloomed,” first. To bloom any amount of sheet gelatin, soak it in a small bowl of cold water. The gelatin is bloomed when it has become soft, after about 2 minutes. If the gelatin still has hard bits to it, it needs to bloom longer. If it is so soft it is falling apart, it is overbloomed; discard the gelatin and start over. Gently squeeze the bloomed gelatin to remove any excess water before using.

To bloom powdered gelatin (any amount between 1/2 teaspoon and 2 teaspoons), sprinkle it evenly onto the surface of 2 tablespoons of cold water in a small cup. If you pour the powdered gelatin into a pile on top of the water, the granules in the center will remain hard and will not bloom. If you use too much water to bloom the gelatin, it will dilute the flavor of the recipe and its consistency will be looser than intended. Allow the granules to soften entirely in the cold water for 3-5 minutes. Once it is bloomed, in order to incorporate either kind of gelatin into a mixture, you need to dissolve the gelatin in hot, but not boiling, liquid — usually a bit of whatever it will be mixed into. If the gelatin gets too hot, it will lose its strength and you will have to start over again.

To prepare the chocolate crumb, preheat the oven to 300°. Combine the flour, cornstarch, sugar, cocoa powder and salt in the bowl of a stand mixer fitted with the paddle attachment and paddle on low speed until mixed. Add the butter and paddle on low speed until the mixture starts to come together in small clusters. Spread the clusters on a parchment- or Silpat-lined sheet pan. Bake for 20 minutes, breaking them up occasionally. The crumbs should still be slightly moist to the touch at that point; they will dry and harden as they cool. Let the crumbs cool completely before using in a recipe or eating. Stored in an airtight container, they will keep fresh for 1 week at room temperature or 1 month in the fridge or freezer.

Once you are ready to assemble your cake, prepare the coffee frosting. Combine the butter and confectioners’ sugar in the bowl of a stand mixer fitted with the paddle attachment and cream together on medium-high for 2-3 minutes, until fluffy and pale yellow.

Meanwhile, make a quick coffee milk:  whisk together the milk, instant coffee, and salt in a small bowl.

Scrape down the sides of the bowl with a spatula. On low speed, gradually stream in the coffee milk. You are essentially forcing liquid into fat, so be patient. The butter mixture will clump up and separate upon contact with the coffee milk. Do not stream more coffee milk into the butter mixture until the previous addition is fully incorporated; keep the mixer on and remain patient. The result will be a wildly fluffy coffee frosting, pale brown and super-shiny.

To assemble the chocolate chip layer cake, put a piece of parchment or a Silpat on the counter. Invert the cake onto it and peel off the parchment or Silpat from the bottom of the cake. Use the cake ring to stamp out 2 circles from the cake. These are your top 2 cake layers. The remaining cake “scrap” will come together to make the bottom layer of the cake.

Clean the cake ring and place it in the center of a sheet pan lined with clean parchment or a Silpat. Use 1 strip of acetate to line the inside of the cake ring. Put the cake scraps inside the ring and use the back of your hand to tamp the scraps together into a flat even layer. Dunk a pastry brush in the passion fruit puree and give the layer of cake a good, healthy bath of half of the puree. Use the back of a spoon to spread half of the passion fruit curd in an even layer over the cake. Sprinkle half of the chocolate crumbs evenly over the passion fruit curd. Use the back of your hand to anchor them in place. Use the back of a spoon to spread one-third of the coffee frosting as evenly as possible over the chocolate crumbs.

With your index finger, gently tuck the second strip of acetate between the cake ring and the top 1/4 inch of the first strip of acetate, so that you have a clear ring of acetate 5 to 6 inches tall — high enough to support the height of the finished cake. Set a cake round on top of the frosting, and repeat the process for layer 1 (if 1 of your 2 cake rounds is jankier than the other, use it here in the middle and save the prettier one for the top).

Nestle the remaining cake round into the frosting. Cover the top of the cake with the remaining frosting. Give it volume and swirls, or do as we do and opt for a perfectly flat top. Garnish the frosting with the mini chocolate chips. Transfer the sheet pan to the freezer and freeze for a minimum of 12 hours to set the cake and filling. The cake will keep in the freezer for up to 2 weeks.

At least 3 hours before you are ready to serve the cake, pull the sheet pan out of the freezer and, using your fingers and thumbs, pop the cake out of the cake ring. Gently peel off the acetate, and transfer the cake to a platter or cake stand. Let it defrost in the fridge for a minimum of 3 hours. (Wrapped well in plastic, it can be refrigerated for up to 5 days.) Slice the cake into wedges and serve.

YIELD:  Makes 1- 6″ layer cake, 5 to 6 inches tall; serves 6 to 8