Birthday Cake #3 - Double Chocolate Mousse Cake

This Double Chocolate Mousse Cake was the third birthday cake that I made in September. It was the second birthday cake that I made to celebrate my elder girl's 13th birthday. She loves chocolate and green tea. So, the best birthday cake for her would naturally be a chocolate-matcha cake.

 

 

 

  

I have not tried my hand on making mousse cake. When I chanced upon this triple chocolate mousse cake, I bookmarked it immediately as the steps sounded manageable for me and it will be a perfect birthday cake for my girl if I replace the bottom chocolate cake with a matcha cake!
 

 

 

I am very pleased with the end result. In fact, quite proud of it. This is the beauty of baking, when you created something that you are satisfy with and  your family/friends also enjoyed eating it, you will be at cloud nine!

 

 

 

For the Matcha Cake Base

(Adapted from this green tea swiss roll recipe. I halved the portion as below for a 8-inch round cake)

 

Ingredients:

• 13g unsalted butter, melted
• 42g egg yolk (about 3 small-medium egg yolks)
• 12g caster sugar
• 4g green tea powder
• 60g egg white (about 2 small-medium egg whites)
• 40g caster sugar
• 24g cake flour, sifted

 

Steps: 

1. Whisk egg yolks and sugar over a pot of hot water till thicken and pale in color.
2. Add in the matcha powder and stir well to combine. Set aside.
3. In another clean bowl, beat egg whites on high speed until foamy, gradually add in sugar and beat till glossy and soft peaks form.
4. Spoon 1/3 portion of egg whites mixture and mix with the egg yolk mixture using a hand whisk. Then gently fold in the remaining egg white using a spatula until well combined.
5. Gently fold the sifted flour into the batter. Add the melted butter into the batter and mix well.
6. Pour the batter into 8-inch round baking pan lined with baking paper. Spread evenly with a scraper. Gently knock the tray on tabletop to remove air bubbles trapped in the batter.
7. Bake in preheated oven at 175 degree C for around 10 minutes.
8. When cake is done, remove from pan and place on a wire rack to cool.

 

For the Chocolate Mousse

(Adapted from this Triple Chocolate Mousse Cake recipe, also halved the portion, as listed below)
 

Dark Chocolate Mousse:

• 3/4 tsp powdered gelatin
• 1 tbsp water
• 1/4 cup whole milk
• 3 oz good quality dark chocolate, finely chopped
• 150ml whipping cream

White chocolate mousse:

• 3/4 tsp gelatin powder
• 1 tbsp water
• 1/4 cup whole milk
• 3 oz good quality white chocolate
• 100 ml whipping cream

Steps:

1. Place 1 tbsp water in a small bowl. Sprinkle gelatin power evenly over the water to let it bloom.
2. Heat the milk to a simmer in a small sauce pan.
3. Pour the hot milk gently oven the gelatin. Stir gently until it’s completely dissolved.
4. Pour this milk mixture over the finely chopped chocolate. Let it sit for 2 minutes. Then whisk to dissolve the chocolate. Let the chocolate sit over a pot of simmering water and stir if necessary to melt the chocolate completely.
5. Whip the cream to soft peak stage. Keep chill until ready to use.
6. Scoop 1/3 of the whipped cream into the melted chocolate and stir to combine so as to lighten up the chocolate. Gently fold in the other 2/3 of the cream.

Repeat the same steps to make the white chocolate mousse.

 

The above yielded 1 cup (about 250ml) of dark chocolate mousse and the same quantity of white chocolate mousse.

 

To assemble:

1. Place the matcha cake into a mold. I used a heart-shape cake ring to cut the cake. Leave the cake in the cake ring.
2. Pour the first layer of dark chocolate mousse slowly over the top of the cake base. 
3. Leave it in the freezer for 10-30 minutes to set.
4. Remove from freezer and gently cover the dark chocolate mousse with the white chocolate mousse. I used a spoon to do this so as not to "disturb" the nicely set dark chocolate layer.
5. Freeze the mousse cake in the freezer for a few hours before serving. (I left it in the freezer over night)
6. 2 hours before serving, remove the cake from the freezer and gently remove the cake ring (I used a hot towel to wrap around the ring to loosen the cake and carefully lift up the ring). Once ring is removed, leave it in the fridge to thaw.

Decorate as desire before serving.