Cut parchment paper to line cake pans and grease well.
Sift the 2 cups cake flour, 1 1/2 cups granulated sugar and 2 1/2 teaspoons baking powder into a medium sized bowl.
In a large mixing bowl that has been chilled, beat 1 cup cold heavy whipping cream with a mixer on high until soft peaks form. Add in 2 teaspoons vanilla extract
In a separate large mixing bowl, place 3 egg whites, room temperature and 1/2 teaspoon cream of tartar. Using a mixer, mix on high until stiff peaks form.
Using a spatula, gently fold the sifted dry ingredients into the whipped cream and alternate with the 1/2 cup cold water (scooping from the bottom-up), in three separate additions beginning and ending with the dry ingredients until combined.
Using a spatula, gently fold in the beaten egg whites into the batter (scooping from the bottom-up), in three separate additions until no streaks of egg whites are visible.
Divide batter evenly into prepared cake pans and allow to sit for 5 minutes, then gently tap on the counter to release large air pockets.
Bake at 350°F for 22-25 minutes until a toothpick inserted in the center of the cakes comes out clean. Do not overbake.
Allow to cool in cake pans no longer than 10 minutes, then turn out onto wire rack to cool completely before assembling cake. Remove parchment paper from cake layers before assembling.