vanilla birthday cake

ingredients 2 2/3 cups cake flour 1 1/2 tsp baking powder 1/2 tsp salt 1 stick salted butter, room temperature 1 stick unsalted butter, room temperature 2 cups granulated sugar 4 egg whites 2 tbsp vanilla paste (my favorite, but you can use vanilla extract if you don’t have paste – but really, i think the…