Separate the egg yolks and egg whites into 2 different bowls. Set aside.

In a large bowl, sift together the dry ingredients: all-purpose flour, cornstarch, matcha, and baking powder. Set aside.

Preheat oven to 350?F/177?C. Line an 8" by 4" loaf pan with parchment paper.

In a clean stand mixer bowl fitted with a whisk attachment, transfer the egg whites and whip until foamy. Add in the cream of tartar and keep beating until lots of bubbles form.

Gradually add in 50g of granulated sugar and whip until stiff peaks form.

Remove the whipped egg whites and transfer to a large clean bowl. Set aside.

Using the same mixer bowl with a paddle attachment, add in the butter and remaining 100g granulated sugar. Cream until light and fluffy, about 2-3 minutes on high speed.

Gradually add in the egg yolks one by one, then slowly add the milk and vanilla extract. Beat until combined.

Sift about ? of the dry ingredients over the egg yolk batter. Fold in the dry ingredients into the mixture and alternate with ? of the whipped egg whites, repeating until combined and no white streaks remain, being careful not to overmix.

Transfer the cake batter to the lined loaf pan. Carefully tap the pan a few times to release any trapped air bubbles.

Bake at 350?F/177?C for 60-65 minutes, until golden brown on top or a toothpick inserted comes out clean.

Let cool completely before slicing.