Preheat your oven to 355°F (180°C) and prepare a hot water bath for warming eggs.

Line your cake pan or coat it lightly with butter and flour, then sift together the cake flour and matcha powder.

Warm the whole eggs and sugar in a water bath, mixing constantly, until the mixture feels warm to the touch.

Whip the egg and sugar mixture on high speed until it becomes very fluffy and forms slow-flowing ribbons, then whip on low speed until shiny to refine air bubbles.

Gently fold in the sifted cake flour and matcha powder until no dry streaks remain.

Add the milk and oil, folding carefully until fully incorporated and the batter flows smoothly.

Immediately pour the batter into the prepared pan and bake at 355°F (180°C) for approximately 25-35 minutes for a 6-inch cake, or 15 minutes for cupcakes, adjusting time as needed for your oven.

Once baked, immediately flip the cake out of the pan and let it cool completely before slicing to ensure the best texture.