In a medium bowl, sift together the flour, baking powder, baking soda and salt. Set aside.
In the bowl of your mixer, beat the butter until creamy. Add the sugar and beat again for about 3-5 minutes on medium high speed until it turns white and fluffy. Add in the egg whites one at a time and mix on medium until each one is fully mixed in.
Add the extracts, milk, sour cream and vinegar to the butter mixture and mix on medium speed until combined. Add the dry ingredients and mix until jut combined.
Separate the cake batter evenly into the two cake pans and bake for about 25-30 minutes, until a toothpick comes out clean and the center of the cake springs back when lightly pressed.