1.   Prepare the flourless chocolate cake as per recipe: https://www.youtube.com/watch?v=s6zbxwRfNCE . Let cool completely before using as a base for the mousse layers

2.   Make the white chocolate base by adding all the ingredients, except the gelatin and water, to a medium bowl

3.   Place the bowl over a small saucepan which has simmering water set over low heat (a bain-marie). Stir as the ingredients melt. Cook until everything is completely melted. Turn off the stove element. Remove bowl from the pot and set aside

4.   Meanwhile, dissolve the gelatin in the water and let gelatin swell. Place the glass with the gelatin into the hot water, stir occasionally until liquid is clear and melted

5.   Pour the gelatin into the white chocolate and mix well. Divide the white chocolate mixture into two equal amounts

6.   Dissolve the matcha powder in water, stir to form a paste and pour into one of the two bowls of white chocolate, while still warm. Whisk to combine very well and set aside

7.   Let both the matcha bowl and the bowl with the white chocolate cool completely to room temperature

8.   Whip the first 225 g of whipping cream until stiff peaks form. Add to white chocolate and fold together, until well combined

9.   Pour the white chocolate mousse over the flourless chocolate cake (still in the spring form pan). Refrigerate for about 20 minutes to firm up

10.   Whip the second batch of cream and add it to the matcha white chocolate bowl. Fold together until well combined

11.   Get the cake with the first two layers out of the refrigerator and pour the matcha white chocolate mix on top

12.   Refrigerate for about 4 to 6 hours or overnight

13.   OPTIONAL: Garnish as you choose. Simplest way is to sprinkle a fine layer of matcha tea on top, or decorate with white chocolate or fruit of your choice such as strawberries, raspberries or blueberries. Enjoy!