Whisk Large Egg (3) Yolks in a bowl. Set whites aside. Add Caster Sugar (28 gram) and whisk well.
Add Vegetable Oil (3 tablespoon) and Water (4 tablespoon), then whisk until combined.
Sift the Cake Flour (75 gram), Matcha Powder (2 1/2 teaspoon), and Baking Powder (1 teaspoon) into the egg yolk mixture gradually, folding it in until incorporated.
Preheat oven to 340 degrees F (170 degrees C).
Beat egg whites on low speed in a separate bowl until mixture becomes white and foamy.
Add the Caster Sugar (57 gram) in 1-minute intervals while beating on high speed, until stiff peaks form.
Add the meringue 1/3 at a time to the cake batter base, folding it in very gently each time.
Pour into the chiffon cake pan and mix with chopsticks to remove any air pockets.
Bake for 30 minutes.
Cool the cake before removing from the pan gently.
Sprinkle cake with Powdered Confectioners Sugar (to taste) before serving. Enjoy!