Cake Flour: What is it? It's a clear path to lovely soft cakes, and I'm going to show you how to make it.
Substituting cake flour with a mix of all-purpose flour and cornstarch works because the cornstarch helps inhibit the formation of some of the gluten in the all-purpose flour. The result? A cake that's just as tender as it would be if you used store-bought cake flour. Just be sure to sift your pseudo-cake flour well: you want the cornstarch to be thoroughly combined with the flour and the mix to be light and airy.