Watermelon Skin Matcha Roll Cake

 Roll cakes have always been our favourite cakes, as they are made of soft and spongy cakes. With the most basic double cream filling and some fresh fruit ( or any fillings) that even enhance the whole enjoyment of it. I have seen a few of our bloggers did this watermelon skin roll cake from the roll cakes recipe book by 孟老师。And I know many of our home bakers have this particular copy or even all the collection of her series. It is definitely worth buying the book as the recipe produces great results!

The green tea sponge is absolutely soft and spongy, which it doesn't make you feel too guilty to have more than what you wish. I really enjoyed every piece of it. I didn't follow the filling of the original recipe for the roll cake as I find it too much work to make the custard like kind of cream. So I did it the quick and lazy way - just double cream and fresh strawberries.


Ingredients:

Watermelon skin :
Unsalted butter   15g
icing sugar  10g
egg white  15g
Top flour  10g
Matcha powder  1/2tsp

* Mix all ingredients to get a thick paste. Use a piping bag and fill it with the thick paste and set a side.


Sponge:

Unsalted Butter   25g  (melted)
yolk  4
matcha powder  4g
caster sugar  25g

Egg white   3
caster sugar  60g

Top Flour   45g

Method:

1. Cut a very small hole of the piping bag that filled with thick paste, and pipe straight lines on a Swiss roll baking tray ( I used  28cm x28cm) lined with parchment paper. Use a tooth pick and drag short lines on each left and right side of each line to create the watermelon skin effect. Put the tray in the fridge after this step is done.

2. In a clean mixing bowl, whisk yolks and sugar till foamy then add in matcha powder. Mix well.

3. In another mixing bowl, whisk egg whites till foamy then slowly add in the sugar and continue to whisk till soft peak.

4. Slowly add in the egg white to the yolk batter and gently mix them well, and then sift in the top flour. Take a small portion of the batter to mix with the melted butter and return the butter mixture to the main batter and carefully mix till well blended . Pour batter over the prepared Swiss roll baking tray and even out the batter.

5. Bake in a pre heated oven for 12 minutes at 160'c. Once cake is baked, carefully pull out the parchment paper and place the paper over the sponge and let it cool.

6. Whip up the double cream and cute some strawberries for the cake filling. Chill the cake after it's filled and rolled up.