Chocolate Chip Layer Cake with Passion Fruit Curd

Ingredients

For the passion fruit curd:

100 grams (½ cup) passion fruit puree
65 grams (1/3 cup) granulated sugar
2 large eggs
2 tsp. water
½ tsp. powdered gelatin
170 grams (12 tbsp.) butter, very cold
2 grams (½ tsp.) kosher salt

For the chocolate crumb:

52 grams (1/3 cup) flour
2 grams (½ tsp.) cornstarch
50 grams (¼ cup) granulated sugar
33 grams (1/3 cup) cocoa powder
2 grams (½ tsp.) kosher salt
43 grams (3 tbsp.) butter, melted

For the cake:

15 grams (8 tbsp.) butter, at room temperature
250 grams (1¼ cup) granulated sugar
60 grams (¼ cup tightly packed) light brown sugar
3 large eggs
110 grams (½ cup) buttermilk
75 grams (½ cup) grapeseed oil
12 grams (1 tbsp.) vanilla extract
185 grams (1½ cups) cake flour
4 grams (1 tsp.) baking powder
4 grams (1 tsp.) kosher salt
150 grams (¾ cup) mini chocolate chips

For the frosting:

115 grams (8 tbsp.) butter, at room temperature
40 grams (¼ cup) confectioners’ sugar
55 grams (¼ cup) milk
1.5 grams (¾ tsp.) instant coffee powder
1 gram (¼ tsp.) kosher salt

To assemble:

60 grams passion fruit puree
40 grams mini chocolate chips

Chocolate Chip Layer Cake with Passion Fruit Curd 7

Instructions

To prepare the passion fruit curd, combine the passion fruit puree and sugar in a blender and process until the sugar granules are completely dissolved. Blend on low until the mixture is a vibrant orange-yellow color. Clean empty the blender canister and transfer the contents of the blender to a medium pot or saucepan. To bloom the gelatin, pour the water into a small basin and sprinkle the gelatin evenly over the top. Heat the passion fruit mixture in a saucepan over low heat, whisking often. As it heats up, it will start to thicken. When it reaches a boil, remove it from the heat and pour it into a clean blender canister. Blend in the gelatin, butter, and salt until the mixture is thick, glossy, and completely smooth. Transfer to a heatproof container, cover, and chill for at least 1 hour, or until totally cold.
Preheat the oven to 300 degrees F for the chocolate crumb. Use a silicone baking mat or parchment paper to line a baking sheet. Combine the flour, cornstarch, sugar, cocoa powder, and salt in the bowl of an electric mixer. Mix on low speed until everything is well incorporated. Add the butter and continue to stir until the mixture forms little clusters. Place the clusters on the baking sheet that has been prepared. Bake for 20 minutes, breaking them up halfway through. Remove the baking sheet from the oven. As the crumbs cool, they will dry and solidify. Before using, allow to cool fully.
Preheat the oven to 350 degrees Fahrenheit for the cake. A quarter sheet pan’s edges should be butter and floured. Using parchment paper, line the bottom of the pan. Combine the butter and sugars in the bowl of an electric mixer. For 2-3 minutes on medium-high speed, beat until fluffy. Scrape down the sides of the bowl, add the eggs, and mix for another 2-3 minutes on medium-high. Scrape down the bowl’s sides once more.
Stream the buttermilk, oil, and vanilla into the mixer on low speed. Increase the speed to medium-high and continue to mix for 4-6 minutes, or until the mixture is virtually white, twice the size of the original batter, and totally homogeneous (there should be no streaks of fat or liquid.) Scrape the bowl’s sides clean. Add the cake flour, baking powder, and salt to the mixer on low speed. 45-60 seconds, just until the batter mixes together and there are no dry streaks. In the prepared quarter sheet pan, spread the batter out evenly. Using a fork, evenly distribute the small chocolate chips throughout the batter.
Bake for 30-35 minutes, turning the pan halfway through baking, or until the cake is puffy and no longer jiggly in the center (the cake should bounce back when lightly poked with your finger.) Allow to cool entirely on a wire cooling rack.
Make the coffee frosting just when you’re ready to finish assembling the cake! In the bowl of an electric mixer, cream together the butter and confectioners’ sugar. On medium-high, cream together until pale and fluffy, about 2-3 minutes. Meanwhile, whisk together the milk, instant coffee, and salt in a small mixing dish. Scrape the sides and bottom of the mixing bowl. Slowly drizzle the coffee milk into the butter mixture while mixing on low speed. The butter mixture will separate and clump together. Wait until each addition has been well mixed before adding more liquid. (This may appear to be a little quantity of frosting, and trust me, you will lament it as you assemble the cake, but do not add more than is asked for otherwise the taste balance of this cake will be thrown off.)
Invert the cake from the sheet pan onto a work area to assemble it. Cut two circles out of the cake using a 6-inch cake ring (these will be the top two layers.) Wipe the cake ring clean and set it in the center of a sheet pan lined with parchment paper or a silpat. Line the interior of the cake ring with a strip of acetate. Place bits of leftover cake in the ring and mash them together to form a flat, equal layer. Soak half of the passion fruit puree into the cake with a pastry brush.
Half of the passion fruit curd should be spread evenly over the cake. Half of the chocolate crumbs should be sprinkled equally over the curd, and the back of your hand should be used to gently attach and secure them in place. Spread one-third of the coffee frosting over the chocolate crumbs as evenly as possible. (Don’t worry if it looks a shambles; it’ll still be delicious.) Place a second strip of acetate between the cake ring and the top 14-inch of the first strip of acetate and gently tuck it in. Repeat the layering technique with another cake round on top of the icing (passion fruit puree, curd, crumbles, frosting.) Place the last cake layer on top of the icing. The remaining frosting should be applied on top, and micro chocolate chips should be sprinkled on top.
Place the completed cake in the freezer for at least 12 hours to allow the cake and filling to firm. Remove the pan from the freezer at least 3 hours before serving, take the cake out of the cake ring, and peel away the acetate layers. Defrost for at least 3 hours before slicing and putting on a cake dish.