Originally Posted by Casp22
I think that is one that I have tried and it is not bad. It is still just a little dense for what I am trying to make. Maybe a scratch cake is just not going to be as light as a box cake.
If you find it too heavy, switch to cake flour.
Another option is to use a southern AP flour such as White Lily. White Lily is sort of midway between actual cake flour and regular AP flour. Don't get the self rising sort.
Failing that, sub in 3/4 cup of your AP and 2 T of cornstarch for each 1 cup of flour called for in the recipe. Yes, I know that is slightly less than 1 full cup, but cornstarch weighs more than flour and I've found this works better than 7/8 c AP flour plus 2 T (1/8th cup) of cornstarch. YMMV.
A cake that uses shortening will tend to be lighter than one that uses butter. If you can lay your hands on High Ratio shortening, it will make it even lighter. Oil cakes tend to be heavy, in my experience. Moist, but heavy. You have oil AND butter in that recipe; if subbing in cake flour or some approximation thereof doesn't help, find a recipe that calls for shortening instead of butter and oil.
If at all possible, find a recipe that gives ingredients BY WEIGHT and not by volume; a little variation in how much flour is actually in your "1 cup" of flour can make a HUGE difference in something as finely balanced as a cake recipe.
Box cakes usually use cake flour and are loaded with additional emulsifiers, tenderizers, etc. Nevertheless you can easily make a light cake from scratch - if you start from the right recipe.