I've searched high and low and I can't seem to find a posting that contained the ingredient (& qty per cup) that I can add to All-purpose flour to make into cake flour.
I have seen 2 Tablespoons cornstarch w/ 3/4 cup all-purpose flour and 1/4 cup cornstarch to 1 3/4 cups all-purpose flour. HTH.
I've done it once with with all purpose flour and cornstarch. It was 2 tbsp cornstarch in the bottom of each cup of flower (then just fill the cup with flour after that), and it worked great for me! Because I've only done it once though, I don't know it's always a fail-proof option...maybe one of the more experienced cakers knows for sure?
Yes this helps
What is the difference in the cake when using cake flour vs. all purpose flour?
Oooo that chart helps too! Thanks!!! Cake Central people are THE BEST!!!