3/4 cup (1½ sticks or 169g) unsalted butter, softened but still cool, cut into cubes
Preheat oven to 350°F. Prepare two 8-inch cake pans. (Use butter and flour, line with parchment paper, or spread GOOP.)
Pour milk, egg whites, and extracts into a medium bowl. Stir with a fork until blended.
In the bowl of a stand mixer, mix cake flour, sugar, baking powder, and salt. Mix on low speed (just to sift and incorporate ingredients). Add butter, cut into cubes, and continue beating on low for about 1-2 minutes.
Add all but ½ cup of the milk mixture to the flour mixture and beat at medium speed for 1½ minutes. Add the remaining ½ cup of the milk mixture and beat for about 1 minute.
Pour batter evenly between two prepared cake pans (approximately 2¾ liquid cups or 612 grams per pan).
Bake until a toothpick inserted in the center comes out with a few crumbs and has no wet batter clinging to it, about 27 to 30 minutes.
Allow cake to cool in pan about 5 minutes then carefully flip onto a cooling rack to cool to room temperature.