Japanese Cream Cheese Birthday Cake

It was my mother's birthday.  I didn't know what to bake... fondant cake, yellow cake, ... actually I wanted to bake a cake like the one they bake at the Hong Kong bakery.  But I decided to do something different.  Since I have been testing with the Japanese cream cheesecake, I modified the recipe to make a cream cheese Birthday cake - half with Matcha and the other half with vanilla flavor.  It turned out good.

Prepare the angel food cake pan 9-3/8" x 4" with removable bottom - spray and lined with parchment paper bottom and side, including the center cone.  Yes, it was challenging.  The side parchment should extend above the rim of the cake pan at least by 2 inches.

Baking Method:  Bain Marie
Cake Pans:  7 x 2-1/2" to bake in and 10" or 12 " cake pan to bake in Bain Marie method
Ingredient:
6 oz butter - soft
8 oz cream cheese
1/2 C milk
5 eggs separated
1/2 C Cake Flour
1/2 C Cornstarch
1/2 tsp Baking Powder
2 Tbsp lemon juice
1 Tbsp lemon zest
1 C sugar - divided - 1/4 C for egg white, 1/4 C for cheese mixture, 1/2 C for egg yolks
1 Tbsp Vanilla Paste
1 tsp of cream of tartar
Boil 3 Cups of water to rolling boil -- for Bain Marie
1 Tbsp Japanese Matcha

Pre-heat oven to 400'F right when starting to beat egg white.

Whip cream cheese and milk + sugar + Vanilla paste + lemon juice and lemon zest together.  Set aside.
Whip egg yolks and start adding sugar 1 Tbsp at a time and beat until pale in color.
  Set aside, keep covered.
Sift cornstarch mixed with cake flour together and set aside.   **Preheat oven to 400'F
In a clean mixing bowl, whip egg white with 1 tsp of cream of tartar.
Whip till silky and medium peak is formed.
Transfer cheese mixture into a large surface mixing bowl.  Add egg mixture and Fold till smooth.
Sift flour mixture into the egg/cheese mixture.  Fold well.
Add 1/4 of whipped egg whites in and lighten the batter.
Add the remaining egg whites. Fold "gently" all around till nice and smooth.
Transfer 1/2 of the vanilla batter into the prepared cake pan.
Smooth the top.
In a small bowl, add Matcha and 1/4 C of batter and mix well.
Fold the Matcha mixture to the remaining batter.  Fold gently until mixed.
Pour into the top half of the cake pan.  Smooth the top.
Place the cake pan in a large 12" cake pan. 
Place in the oven.
Carefully pour hot water half way , but be sure not to go over the lowest rim of the aluminum foil that is wrapped around the cake pan, if there is one.
Bake 30 min at 400'F, then drop the temperature to 380'F and bake for 15 min.  Then 350'F for 15 min and bake till internal temperature rise to 180'F and tester comes out dry.
Turn off the oven.
Remove from Bain Marie.
Remove from oven to cool.
Store in refrigerator.
Invert to the serving plate or cake cardboard. and Invert it back again.
Decorate with Whip cream.
Serve.