Dark Chocolate Mousse Cake
A luxurious dessert blending rich chocolate with an airy mousse, perfect for special occasions and impressing guests.
Ingredients
For the cake
- 1 Cup All-Purpose Flour 120g
- ½ Cup Dutch Cocoa Powder 42g
- 1 Teaspoon Fine Espresso Powder optional, but recommended
- ¾ Teaspoon Baking Powder
- ½ Teaspoon Baking Soda
- ½ Teaspoon Fine Sea Salt
- 1 Cup Granulated White Sugar 200g
- 1/3 Cup + 1 Tablespoon Neutral Oil (avocado, vegetable, canola) 80g
- ⅓ Cup Full-Fat Sour Cream (room temperature) 76g
- 1 Whole Large Egg (room temperature)
- 1 Teaspoon Pure Vanilla Extract
- ½ Cup Boiling Water
For the mousse
- 1 ½ Cups Heavy Cream
- 1 Whole Large Egg
- 1 Large Egg Yolk
- ⅓ Cup White Granulated Sugar 67g
- ¼ Cup Dutch Cocoa Powder 21g
- 1 Teaspoon Fine Espresso Powder
- 1/8 Teaspoon Fine Sea Salt
- 6 Ounces Dark Chocolate 170g
- 1 Teaspoon Pure Vanilla Extract
- 1 Cup Heavy Cream (to be whipped) (cold) 227g
For the ganache
- 5 Ounces Dark Chocolate (60% to 70% chocolate) 141g
- ⅔ Cup Heavy Cream 151g
Instructions
Prepare the Cake
- Preheat your oven to 350°F (175°C) and grease a round 9-inch cake pan.
- In a large bowl, whisk together the flour, cocoa powder, espresso powder, baking powder, baking soda, and salt.
- In another bowl, mix the sugar, oil, sour cream, egg, and vanilla until smooth.
- Gradually add the dry ingredients to the wet, then stir in the boiling water until well combined.
- Pour the batter into the prepared pan and bake for 30-35 minutes.
- Once done, let it cool completely.
Make the Mousse
- In a saucepan over medium heat, combine heavy cream, egg, egg yolk, and sugar, stirring until warm.
- Whisk in the cocoa powder, espresso powder, and salt, bringing the mixture to a gentle simmer.
- Remove from heat and stir in chopped dark chocolate and vanilla until smooth.
- Let it cool slightly before whipping the cold cream until soft peaks form, then fold it into the chocolate mixture until incorporated.
Assembly
- Once the cake is cooled, slice it in half horizontally.
- Place one layer back in the pan and pour half of the mousse over the top.
- Add the second layer and top with the remaining mousse.
- Chill for at least 3 hours, or until set.
Finish with Ganache
- Melt the dark chocolate in a double boiler.
- Stir in the heavy cream until smooth.
- Pour over the chilled mousse cake, allowing it to drip down the sides.
- Chill again until the ganache is set.
Notes
Ensure your heavy cream is chilled for whipping for fluffy peaks! Don’t skip the espresso powder; it amplifies the chocolate flavor without making it taste like coffee. When folding the whipped cream into the mousse, be gentle to maintain that airy texture.