Watermelon mousse cake i saw this video on youtube a while back.. but it’s a silent movie…. so I adapted the matcha cake roll recipe from Junko’s book for the “melon skin”

swiss roll ingredients

4 eggs (separated into 1 egg white, 3 egg whites, and 3 egg yolks. There will be an unused egg yolk)
2 tsp matcha powder (dissolved in 60ml of hot water)
65g castor sugar
40ml canola/salad oil
Vanilla extract (recipe stated as appropriate. I added 1tsp vanilla extract)
80g cake flour (for cake)
1 tsp corn starch

Painting of watermelon stripes
2tsp matcha powder

Watermelon mousse ingredients (recipe adapted from here)
1 cup (250ml) watermelon puree
1 1/2 powdered gelatine
1/8 cup cold water
1/4 cup sugar
2tsp lemon juice
1/4 tsp pure vanilla extract
1/2 cup cold pouring cream

Watermelon mousse cake

– line 25 x 25cm baking pan with parchment paper
– whisk egg yolks and 35g of the castor sugar till pale and frothy
– Add water, salad oil and vanilla extract, and mix well. Sift cake flour into mixture and whisk till ribbon stage
– in a clean mixer bowl, beat ONE egg white till frothy. Then add in a pinch of the corn starch, and continue beating till you achieve stiff peak
– in a separate bowl, add 2tsp matcha powder to 4tsp of green tea egg yolk mixture (as my melon stripes are thick)
– add 3tbsp of egg white meringue to the above and mix well. Place mixture into piping bag and pipe stripes onto the middle portion of parchment paper
– bake for 2 mins in preheated oven of 170 degrees C (if your stripes are thinner, you can bake for 1 min). Remove from oven and set aside
– meantime, beat 3 egg whites and before you achieve soft peak stage (i.e. between frothy and soft peak stage), add in the remaining egg white from the earlier process. Continue beating till you achieve slightly stiff peak. Add in the remaining 30g castor sugar. Beat till you achieve a shiny texture and add in the remaining corn starch and continue beating till stiff peak
– fold in meringue in 3 additions to egg yolk mixture
– carefully spread the cake mixture onto baking tray
– bake for 14 mins (I baked for 20mins)
– remove tray from oven, and flip the cake over carefully onto a clean baking paper (so that the designs are facing the top). Remove the parchment paper from the design very very carefully. Leave paper on top of design and leave cake to cool
– after cake has cooled, slice off the portion of the cake to the size of the cake mould. You can see the cake mould in the youtube video above. It is a semi-circle log-shaped pan (24cm in length)
– place cake with design faced down on a piece of parchment paper and place cake (together with paper) into mould
Watermelon mousse cake
Mousse Preparation
– Meantime, prepare mousse – place gelatine and cold water in a small bowl to allow the gelatine to soften
– Place watermelon puree in a medium saucepan with sugar and lemon juice and heat on low until the sugar dissolves completely
– Add softened gelatine to the mixture, heat and stir until the gelatine dissolves completely
– Remove from the heat and chill mixture in fridge until it reaches around room temperature and is starting to thicken
– Whip cream in a large mixing bowl to soft peaks. Add vanilla to watermelon mixture and then fold whipped cream until all the lumps are removed
– Pour mousse on top of cake and chill in fridge. I chilled it overnight for it to firm up so it does not get too messy when slicing
– In the video, the baker added “sunflower chocolate seeds” into the mousse before adding to the cake. I preferred smaller looking seeds, and decorated the cake with chia seeds on the sliced cake

I am submitting this post to Aspiring Bakers #32: World of Mousse Cake (June 2013) hosted by Hankerie. Do hop over to her blog ~ she has a very pretty and interesting blog with lots of creative bakes



Pollution index: 195 (unhealthy ~ 4 days in a row I haven’t seen the sun)


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