Triple-Layer Chocolate Cake with Cocoa Soak and Fudge Frosting

Method12 steps · about 1 day 1 hr 30 min

1. 1

   Step 1: Make the frosting a day ahead, because it needs to set overnight, ideally for 24 hours, before you can frost the cake. Sift 180 g cocoa powder into the bowl of a stand mixer fitted with the paddle attachment, or into a large bowl if you're using a hand mixer. In a medium saucepan over medium heat, melt 84 g butter with 3/4 tsp salt. Whisk in 435 ml heavy cream and 300 g sugar. Keep cooking and whisking occasionally until the mixture is hot and just beginning to simmer. Reduce the heat to low and whisk in 128 g chocolate chips until completely melted and smooth, about 5–8 minutes.

   Uses 180 g cocoa powder, sifted · 84 g unsalted butter · 3/4 tsp fine sea salt · 435 ml heavy whipping cream · 300 g granulated sugar · 128 g semi-sweet chocolate chips

2. 2

   Step 2: Slowly stream the hot chocolate mixture into the bowl of sifted cocoa powder, mixing with the paddle until combined. Scrape down the bowl, then increase the speed to medium and mix for 2–3 minutes, until smooth and lump-free. Mix in 1 tsp vanilla until fully incorporated.

   Uses all the hot chocolate mixture · the sifted cocoa powder in the mixer bowl · 1 tsp vanilla bean paste or extract

   
3. 3

   Step 3: Transfer the frosting to an airtight container and leave the lid off while it cools to room temperature. Then cover it and leave it at room temperature to set overnight, ideally for 24 hours. If you're short on time, refrigerate it for 6–8 hours instead. Bake the cake while the frosting finishes setting, so the layers have cooled completely by the time you assemble.

   Uses all the fudge frosting

4. 4

   Step 4: When you're ready to bake, preheat the oven to 162 °C. Lightly grease three 20 cm round cake pans and line the bottoms with parchment paper. In a stand mixer bowl, combine 240 g cake flour, 300 g sugar, 100 g brown sugar, 1 1/2 tsp baking powder, 3/4 tsp baking soda and 1 tsp salt. Mix in 98 g cubed room-temperature butter on low speed for about 3 minutes, until the mixture looks like coarse sand.

   Uses 240 g cake flour · 300 g granulated sugar · 100 g brown sugar · 1 1/2 tsp baking powder · 3/4 tsp baking soda · 1 tsp fine sea salt · 98 g cubed room-temperature butter

   
5. 5

   Step 5: In a bowl with a spout, whisk 235 ml hot brewed coffee with 75 g cocoa powder until smooth. Then whisk in 228 g sour cream, 120 ml milk, 2 eggs, 80 ml vegetable oil and 2 tsp vanilla.

   Uses 235 ml brewed coffee · 75 g cocoa powder · 228 g sour cream · 120 ml whole milk · 2 large eggs · 80 ml vegetable oil · 2 tsp vanilla bean paste or extract

6. 6

   Step 6: Add half of the wet mixture to the mixer bowl and mix on low speed until a smooth, pasty batter forms. Scrape down the bowl. Add the remaining wet mixture and mix until a smooth, thin batter forms, scraping down the bowl as needed.

   Uses all the flour and butter crumb mixture in the mixer bowl · all the coffee, cocoa and sour cream mixture, added in two halves

   
7. 7

   Step 7: Divide the batter evenly among the three prepared pans, about 525 g per pan. Bake at 162 °C for 20–30 minutes, until a toothpick inserted into the center comes out covered in a few moist crumbs.

   Bake cake layers · 30 minUses all the cake batter, about 525 g per pan

   
8. 8

   Step 8: Let the pans cool on a wire rack for 25 minutes. Run an offset spatula around the sides of each pan and flip out the cake layers. Let the layers finish cooling completely on the wire rack before frosting.

   Cool in pans · 25 minUses 3 baked cake layers in their pans

9. 9

   Step 9: While the layers cool, make the soak: in a small pot, combine 65 ml water, 12 g cocoa powder, 40 g sugar and 1 tsp vanilla. Cook over medium heat until boiling, then reduce the heat to low and cook 2–3 minutes longer, until thickened. Let it cool before using.

   Uses 65 ml water · 12 g cocoa powder · 40 g granulated sugar · 1 tsp vanilla bean paste or extract

10. 10

    Step 10: Once the frosting has set, paddle-mix it on medium to high speed for 30–60 seconds to loosen it to a spreadable consistency. If it was refrigerated, let it sit at room temperature for a few hours first.

    Uses all the set fudge frosting

11. 11

    Step 11: Place the first cake layer on a serving plate or cake stand and slice a thin layer off the top with a serrated knife. Brush it with about 1 tbsp of the cocoa soak, then spread about 120 ml of the frosting on top. Place the second layer on top and repeat with another 1 tbsp of soak and about 120 ml of frosting. Top with the final layer upside down for a flat surface. Chill for 20 minutes to set the layers.

    Chill layers · 20 minUses 3 cooled cake layers · about 2 tbsp of the cooled soak (1 tbsp per layer) · about 240 ml of the loosened frosting (120 ml per layer)

    
12. 12

    Step 12: Frost the outside of the cake with the remaining frosting. Garnish with chocolate sprinkles or chocolate pearls and any remaining cake soak if desired.

    Uses the chilled stacked cake · all the remaining frosting · any remaining cake soak, optional · chocolate sprinkles or pearls, optional