Cake flour? Sigh...I have the regular stuff (AKA AP flour) What is cake flour anyways? And why do i need to use it? Well, although you can normally use all-purpose flour in many recipes, it's a blend of high-gluten hard wheat and low-gluten soft wheat. It is also pre-sifted, so you can just stir it, then spoon directly into your measuring cup
Cake flour is finely ground and bleached, so it has a fine, delicate texture. And it easily absorbs fats such as butter. Cakes made with cake flour have a finer texture than those made with all-purpose flour.
So what do you do when you don't have it or you run out of it?
Measure out the amount needed for your recipe.
For every 1 cup of flour remove 2 Tbsp of flour.
Now add 2 Tbsp of Cornstarch for every 1 cup of flour. (replacing the tablespoons of flour taken out).
Always measure the flour that is needed after its sifted.