Japanese cocoa cotton cheesecake - by Kim Heahsk

Japanese cocoa cotton cheesecake 
(original recipe from Fiona Lau but i modify it with cocoa powder)

(A)
Cream Cheese 200g
Fresh Milk 128g
Butter 46g
Egg Yolk 4
cocoa powder 2tsp
(B)
Cake flour 26g
Corn flour 14g
(sieved together)
(C)
Egg White 4
Fine sugar 80g
Cream of tartar 1/4 tsp
Method:  
1) Dissolve cocoa powder with warm milk 1st then double boiled to melt the cream cheese , butter until it smooth.Cool down then add in egg yolks mix well.
2) add in (B) mix well and set aside.
3) Whisk egg white with cream tartar until foamy, add in sugar and continue to whisk until soft peaks form.
4) fold in well 1/3 of white then only pour it into the remaining white and continue to fold well .
5) Pour in 8'X8' square tin and ready to Steam-Bake (water bath) in 160°C preheat oven for 15 minutes then 140°C for another 50~60 minutes until cook.
Notes : For those who loves sweet please add another 10g of sugar. TQ !!