Chocolate Chiffon Cake with Chocolate Swiss Meringue Buttercream

Chocolate Rice Flour Chiffon Cake recipe adapted from here .

Ingredients : for  8" chiffon cake pan 
5 egg yolks
8g caster sugar
40g corn or sunflower oil  
1/8 tsp salt
40g cake flour
20g cocoa powder
30g rice flour 在来米粉/粘米粉
70g chocolate milk

5 egg whites
60g caster sugar
1 tsp lemon juice or vinegar (I only used 1/4 to 1/2)

Method :
1. Sift cake flour, cocoa powder and rice flour twice.
2. Mix egg yolks and sugar in a bowl, whisk till sugar has dissolved.
3. Add in oil, salt and chocolate milk and mix well.
4. Sift in flour mixture and whisk well.
5.In another bowl, beat the egg whites and lemon juice/vinegar till frothy. Add in sugar gradually and beat until approaching stiff peaks (meringue stand straight with a little curve at the tip) or till stiff peaks (this stage is a bit difficult to fold with egg yolk mixture).

6. Use whisk to loosen the egg yolk batter a bit, then take 1/3 of meringue and use a hand whisk to mix well with egg yolk batter.

7. Fold in 1/2 of meringue and use a silicone spatula, gently fold with egg yolk batter till slightly combined. Fold in the balance meringue and gently fold till well combined. 
8. Pour the batter from a considerable height into cake pan, lightly shake it left and right to level the cake, then gently bang the cake pan on the table top to release air bubbles. 

9. Bake at pre-heated oven at 150C at center rack for 25 mins and 160C for 15-20 mins. (I off the top heat element and on it back during the last 15 mins)

10. Remove the cake pan from oven, drop it from high side to prevent the cake shrink too much during cool process.

11. Turn the cake pan upside down and cool completely before remove from the cake pan. 

Swiss Meringue Buttercream (Whole Egg)
210g eggs (4 eggs)
250g sugar
500g butter
1 tsp vanilla extract

300g eggs (6 eggs)
325g sugar
680g butter
1 tsp vanilla extract

400g eggs (8 eggs)
425g sugar
900g butter, hard and cubed
2 tsp vanilla extract


Method :

1. Whisk eggs and sugar over a pot of simmering water (double boil / bain marie) , Keep whisking the mixture.
2. Remove from heat once reach 72C to kill the Salmonella.
3. Move to a bowl of ice water to whisk till the mixture is cooled.
4. Move to attach to stand mixer to whisk till ribbon stage (step 2+3 takes about 15 mins)
5. Change to K beater, add cubed butter, one by one into the mixture,ensure each addition is incorporated before add in next one.
6. Beat until the mixture become smooth and silky. Dun worry is the mixture become curdle, continue to beat or use spatula to fold.

Total times taken to make the buttercream was  about 40-45 mins


Chocolate buttercream for 9" cake
500g buttercream
200g chocolate