This is a delicate and creamy white chocolate mousse cake with a dark chocolate cake base.
Ingredients
Cake Base
- 1/3 cup all-purpose flour
- 1/3 cup sugar
- 3 Tbsp cocoa powder
- ¼ tsp baking powder
- ¼ tsp baking soda
- Pinch salt
- ½ large egg, beaten
- 2 Tbsp milk
- 1½ Tbsp oil
- ¼ tsp vanilla extract
- 2 Tbsp water
Mousse
- 6 tsp gelatin
- 9 Tbsp cold water
- 10 egg whites
- 3 (1/3 cups) whipping cream
- 1½ tsp vanilla extract
- 1 cup milk
- 4½ cups white chocolate (a chocolate bar will work best)
- Blue food coloring
- Chocolate Seashell Truffles
- Blue sanding sugar
- White sprinkles
- White pearl-like candies
- Pink jelly beans
How to Make It
-
Bake the Cake Base
- Preheat oven to 350°F.
- Place the flour, sugar, cocoa powder, baking powder, baking soda, and salt in the bowl of an electric mixer and mix on low speed until fully combined. Add the egg, milk, oil, vanilla, and water and mix until smooth.
- Line the bottom of a 10-inch springform pan with parchment paper and pour the batter into the pan, spreading the batter right to the edges. Bake for 20 to 30 minutes, or until a skewer inserted into the center comes out clean. Place the pan on a cooling rack and cool completely. Remove the cake from the pan and remove the parchment paper lining. Return the cake to the pan and set aside. Make the Mousse
- Sprinkle the gelatin into the cold water and set aside. Beat the egg whites until stiff peaks form.
- In a separate bowl, combine the whipping cream and vanilla extract and beat until soft peaks form. Set both bowls aside.
- Set a small saucepan to medium heat and add the milk. Just before the milk comes to a boil, turn off the heat and add the gelatin and water mixture. Once the gelatin has fully dissolved, add the white chocolate and whisk until fully melted. You may need to turn the heat back on to fully melt the chocolate.
- Add this mixture to the whipped cream and fold to combine (do not use an electric mixer it will deflate the filling!). Then add the egg whites and fold to combine, making sure to keep the mixture as airy as possible.
- Add a couple drops of blue food coloring and gently fold it a couple times, creating a marble effect.
- Pour the mousse into the pan and smooth the surface.
- Place the cake onto a large tray and place in the fridge to chill overnight. Because the filling is quite liquidy, a little bit may leak out from the edges of the pan. To help this, bunch some paper towel around the base of the pan and keep it on the tray while it’s setting in the fridge.
- Run a warm, damp dishcloth around the sides of the pan, then slide a sharp knife along the inside walls of the pan to help loosen the cake. Gently unlatch the sides of the pan and slide it off the cake.
- Decorate the cake with blue sanding sugar, white sprinkles, pink jelly beans, Chocolate Seashell Truffles, and pearl-like candies. Slice and enjoy!