jjjandrbaker wrote:
I have a vague memory of some kind of powdered sour cream that my mother used to buy. It was a package like gravy mix comes in. You whisked it with water and it actually thickened up. I have no idea if it is available anymore. Haven't thought of it in decades. But, if it is still around, it would work for stroganoff.
I also found this on Amazon:
powdered sour cream
I can see where that would be handy, especially if you mix up your dry flavorings in bulk. Herself uses powdered buttermilk to create her own pancake mix.