Matcha Marble Castella aka Kasutera Japanese Sponge Cake

Ingredients:
5 Eggs separated (total weight 250-280g) ~ room temperature
120g Sugar
100g Bread flour ~ sifted
2 tbsp Honey diluted w/2 tbsp hot water
1/2 tbsp Matcha powder diluted w/2 tbsp hot water

Directions:

1. Use bread loaf pan & line the inside with baking sheet.
2. Place egg whites in mixing bowl & beat at high speed (I'm using Kitchen Aid) until foamy.  Add sugar in 2-3 increments until firm peaks form.
3. Add yolks one at a time at medium speed until well combined.   Add sifted bread flour & beat until just combined.
4. Pour in the honey mixture & continue to beat for 1 min.
5. Pour batter through a sieve into a large bowl & measure 120g plain batter into a smaller bowl & mix in the matcha mixture, blend well.
6. Spoon 4 heap tbsp of the plain batter into the middle of the pan then 1 tbsp of the matcha batter on top.   Continue alternately the batter until the finish.
7. Slightly shake the pan together with the baking tray a little & use a skewer to drag into the batter from inside out to form the spider web pattern.
8. Bake at preheated 160C for abt 55 mins or skewer inserted comes out clean.
9. Drop the cake together with a baking tray from a one-foot height onto the countertop to prevent shrinkage.
10. When the cake is cool enough to handle, lift up the parchment paper from the pan.  Peel it off & place onto a fresh piece of parchment paper.
11. Wrap the cake with plastic wrap while it is still warm & leave overnight in the refrigerator to preserve moisture in the cake & flavor to develop.
12. Trim the sides of the cake except for the browned top before serving.