This chocolate tiramisu cake consists of four layers of chocolate sponge soaked in rum & coffee, alternated with a creamy mascarpone filling.
For the chocolate cake:
- 160g (1 1/3 cups) all-purpose flour
- 125g (1/2 cup + 2 tbsp) granulated sugar
- 21g (1/4 cup) dutch process cocoa powder
- 21g (1/4 cup) black cocoa powder
- 1 tsp espresso powder
- 1 tsp baking powder
- 1/2 tsp kosher salt
- 150g (2/3 cup) whole milk, room temp
- 100g (1/2 cup) light tasting extra virgin olive oil
- 2 eggs, room temp
- 1 tsp vanilla extract
- 75g (1/3 cup) freshly brewed hot coffee
For the tiramisu filling:
- 3 eggs, separated
- 150g (3/4 cup) granulated sugar, divided
- 340g (1 1/2 cup) mascarpone, cold
- 56g (1/4 cup) freshly brewed coffee, cooled
- 3 tbsp rum
- Cocoa powder, for dusting
For the chocolate cake:
- Preheat the oven to 350 degrees F. Grease and line a 9" square pan with parchment paper.
- Soak cake strips in ice cold water.*
- In a medium bowl, whisk together the flour, sugar, cocoa powders, espresso powder, baking powder, and salt. Set aside.
- In a large bowl, whisk together the milk, oil, eggs, and vanilla.
- Add the dry ingredients to the wet, and whisk until just combined.
- Lastly, whisk in the hot coffee until fully combined.
- Pour the batter into the prepared square pan. Wrap the cake strips around the pan and bake for about 25 minutes or until a toothpick inserted comes out clean.
- Allow cake to cool completely in the pan.
- Remove the cake and use a serrated knife to cut the cake in half lengthwise, then each of those halves widthwise to create four rectangles measuring 4"x8" roughly. You may need to trim each rectangle even more to fit into your loaf pan.
For the tiramisu filling:
- In a large heat proof bowl, vigorously whisk together the egg yolks and half (75g) of the sugar until light in color and flows off of the whisk.
- Place the bowl over a small pot of simmering water. Frequently whisk the mixture for about 5 minutes or until the sugar has completely dissolved.
- Remove the bowl from the double boiler and place in the fridge to cool for about 10 minutes.
- Once cool, whisk in the cold mascarpone until fully combined. Set aside.
- In a medium heat proof bowl, whisk together the egg whites and remaining (75g) of sugar.
- Place the bowl over the pot of simmering water, and whisk frequently until it reaches 120 degrees F.
- Remove from heat and use an electric mixer to beat until stiff peaks form.
- Using a rubber spatula, gently fold the meringue into the egg yolk mascarpone mixture until just combined.
- Assemble the cake immediately.
- Line a pullman pan or 9x5 loaf pan with parchment paper, leaving the edges hanging over the sides for easy removal.
- In a mug or measuring cup, combine the cooled coffee and rum.
- Place the first cake layer into the pan and generously brush with the rum & coffee.
- Use a 3 tbsp cookie scoop to add 5 scoops of the tiramisu filling, then spread into an even layer. Repeat this until all cake layers have been added.
- Brush the last cake layer with rum & coffee and top with the rest of the tiramisu filling.
- Loosely cover the pan and place in the fridge overnight.
- Just before serving the next day, remove the cake from the pan and generously sprinkle cocoa powder on top. Enjoy!
- Use a cake strip to create a flat cake. Soak these wilton cake strips in ice water before starting the cake batter. Just before baking, wrap the cake strips around the pan. The cold temperature on the outside of the cake will prevent the edges from baking faster than the center, resulting in an evenly baked flat cake.
- Separate the eggs with your hands. The best way to separate an egg and ensure the egg yolk doesn't break is to crack the egg into a shallow bowl, then pick up the egg yolk with your hands. The egg white will easily pull away from the yolk, which you can then place into another bowl.
- Chill the egg yolk-sugar mixture before mixing in the mascarpone. After heating the egg yolk-sugar mixture over a double boiler, stick the bowl in the fridge for about 10 minutes to bring it back to room temperature. This will ensure the mixture stays thick once the mascarpone is mixed in.
- Do not whip the egg whites until the egg yolk mixture is finished. Whipped egg whites will begin to deflate and dry out if left out for more than a few minutes. To avoid this, wait until after you've mixed the mascarpone into the egg yolk mixture to whip the egg whites.
- Use a cookie scoop to portion the filing. To add an even amount of filling to each layer, use a cookie scoop. I used a 3 tbsp scoop and added 5 scoops to each layer.
- Chill the cake overnight. To allow the rum & coffee to soak into the cake layers, and for the filling to thick up, I recommend chilling the cake overnight. But if you're in a rush, chill it for at least 4 hours.
Keywords: tiramisu cake, chocolate tiramisu cake