I bought a huge can of powdered egg whites in the hopes that I can eliminate the need for using up all the yolks any time I want to make a recipe that calls for whites. However, what I'd really like to do is to find a recipe for angel food cake where I can mix everything together ahead of time (egg whites, flour, sugar, cream of tartar) and then just add water - just like the boxed mixes you find in the stores.
I haven't had any luck doing that, but I had hoped someone here might have some ideas. Can I just mix the regular ingredients together, add water, and whip it up? Will the egg whites still whip when mixed with flour and sugar? How does the magic happen when using a boxed mix?