Black & White Mousse Cake

Have you ever wondered how the oreo cookies got their deep dark black colour? Well, the secret lies in the use of  black cocoa powder. It is essentially  a super alkalized cocoa powder. Normal alkalized cocoa powder which is known as Dutch process cocoa powder is made from cocoa beans that have been treated with alkali solution to neutralize their acidity, and thus, creates cocoa powder that is darker in colour and milder and less bitter in flavour as compared to natural cocoa powder which is simply made from ground roasted cocoa beans. The more alkaline it is the darker the cocoa becomes. Hence, from super alkalizing  or extreme Dutch processing you get black cocoa powder. The black cocoa powder is used mostly for its color and not for its flavor. On its own the black cocoa powder has very little cocoa flavor and it leaves a soapy aftertaste - and in my opinion it also tastes like charcoal. Therefore it is recommended that the black cocoa powder  is used mixed with another cocoa powder either natural or regular Dutch process  in your bakings.




Sometime back, on a regular haunt at my local baking supply store I had come across this black cocoa powder for the very first time. It's the darkest blackest cocoa powder I've seen. Coming from a small town some baking ingredients can be really hard to come by. Fearing that it may not  be restocked,  I grabbed a packet eventhough I had no idea what to do with it. Needless to say  it remained stashed away in my kitchen pantry with no purpose until now. Blame it on impulsive (kiasu) buying! Heh. Thanks to Aspiring Bakers I've finally used the black cocoa powder - though I barely made a dent. I made a black chocolate sponge cake, split then layered with white chocolate mousse before finishing off with a covering of shiny black chocolate glaze. I really love the how the cake looked. The visual contrast of the black and white was so striking and mesmerizing. Love it!

This will be my entry for this month's Aspiring Bakers#7 - Chocolate Delight (May 2011) hosted by DG from Tested & Tasted. Do join in the fun and show off your gorgeous bakes!


Black Chocolate Sponge Cake (Adapted from here)
2 large eggs
67g caster sugar

1/2 tbs liquid glucose

1/8 tsp salt 

2 tbs vegetable oil
5g cocoa powder
5g black cocoa powder
53 g cake flour
1/8 tsp baking soda
1 tbs milk

White Chocolate Mousse (Adapted from the cookbook Baking Code by Alex Goh)

50g milk

20g sugar

1 egg yolk

60g white couverture chocolate (melted)
2 tsp gelatine
30g water
140g whipped cream


Chocolate Glaze
1/2 tbs gelatin powder
60g heavy cream
60g granulated sugar
50g water
20g unsweetened cocoa powder
10g black cocoa powder


Method:

Black Chocolate Sponge Cake: Preheat oven to 170°C. Prepare a 6 inch  round baking tin with removable base.Gently warm up vegetable oil, mix in the cocoa powder and the black chocoa powder. Set aside. Whip eggs,caster sugar and salt at high speed until sugar dissolved. Add in the liquid glucose and continue whipping till ribbon stage- (Very important! The mixture must be well beaten till very fluffy and thick. When the beater is lifted, it leaves a riboon like trail that will dissipate into the batter after a count of ten). Sift in  flour and baking soda, mix at medium speed for 20 seconds until just combined.
In another  bowl, take some batter and mix with the cocoa mixture together with the milk until well blended. Pour back into the batter and fold in until well combined. Pour batter into tin and bake for about 25 minutes  or when skewer comes out clean when tested. Remove from oven and cool upside down on a wire rack. Once cooled, remove cake from tin.

White Chocolate Mousse: Bring milk to boil. In a separate bowl, combine egg yolk and sugar. Gradually pour in the boiling milk, mix well. Then pour back into the pan and cook for 1 minute. Remove from heat. Mix in the melted white chocolate and set aside. In a separate bowl, sprinkle the gelatine over the water and set aside for the gelatine to soften. Then place over double boiler and cook until gelatine has completely melted. Now combine the dissolved gelatine with the white chocolate mixture.Cool over ice water to 30°C. Fold in the whipped ceam.

Chocolate Glaze: In a small bowl, sprinkle gelatin over 1 & 1/2 tablespoon water. Set aside to soften. In a saucepan, combine heavy cream, sugar, water and cocoa powder. Bring to a boil. Let boil for 3 minutes. Remove from the heat and add in the softened gelatin. Mix well then sieve. Let cool a while. Once the mixture has thicken, use immediately.

Assembly: Line a 6" removable base cake tin or cake ring with a piece of sponge cake. Pour in half the mousse then lay another piece of sponge cake before topping with the remainder of mousse. Cover and chill in the fridge until the mousse set. Once set, remove the cake tin/cake ring. Make the chocolate glaze then pour over the whole cake to cover. Leave a while for the glaze to set then keep in the fridge to chill before serving. Decorate as desired.