Dark Chocolate Mousse Cake

This dark chocolate cake with chocolate mousse filling is so rich, creamy, and yummy! You can prepare it for the weekend and surprise your family and friends with a nice piece of chocolate cake and a cup of coffee or tea. Plus, it can be a perfect dessert for birthdays, baby showers, anniversaries, and many other special occasions. You will need around 30-40 minutes to prepare it and some extra time for cooling. Here is the recipe:


For the chocolate cake:

  • 1 ¾ cups all-purpose flour
  • ¾ cup cocoa powder
  • 2 cups sugar
  • 1 ½ teaspoons baking powder
  • 1 teaspoon baking soda
  • A pinch of salt
  • 2 eggs
  • ½ cup vegetable oil
  • 1 cup milk
  • 2 teaspoons vanilla extract
  • 1 cup hot water

For the chocolate mousse filling:

  • 1/2 cup hot water
  • 4 tablespoons cocoa powder
  • 2 cups heavy cream
  • 7-ounce dark chocolate
  • 2 tablespoons sugar


  • Dark chocolate ganache – optional, or
  • Cocoa powder, to dust – optional



To make the cake layers:

  • Preheat oven to 350°F/180°C/Gas Mark 4. Grease and flour two 9-inch round baking pans.
  • In a bowl, mix together sugar, flour, cocoa, baking soda, baking powder, and salt. Add milk, eggs, vanilla, and oil and whisk on medium speed for around 2 minutes. Pour in the boiling water (the batter will be thin- and that’s fine). Divide batter into cake pans.
  • Place in the oven and bake for around 30-35 minutes or until a tester inserted in the middle comes out clean. Let cool in the pan for around 10 minutes; then, remove from pans to wire racks and cool completely.
  • When cakes have cooled, take a sharp serrated knife to layer each 9” cake – (cut the cakes evenly in 1/2 horizontally, in order to end up with 4, thin, 9” cake pieces). Set aside.

To make the mousse filling:

  • In a cup of hot water add the cocoa powder and stir to dissolve. In a microwave or a double-boiler, melt the dark chocolate until smooth. Apply cocoa mix to the melted dark chocolate and combine until well incorporated.
  • In a separate bowl, whisk the sugar and heavy cream until stiff peaks form. Place the cream mix to the melted chocolate and combine with a spatula until well incorporated. Now, it’s time to complete the cake:
  • Apply the first cake layer on round serving plate. Add a filling on top of the cake layer. Repeat the procedure with the remaining cake layers, spreading a layer of filling between each cake layer.
  • You can reserve some mousse filling to spread it evenly around the whole outside and top of the cake. Place in the fridge for around 30 minutes to set.
  • Then, remove from the fridge and apply chocolate ganache over the top (if desired). Refrigerate until ready to serve! Slice.