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Is it possible to make Sour Cream at home?
I make yogurt by adding a small amount of yogurt to milk, heating it slightly (barely in this weather!) and letting it sit several hours. It's, of course, a simple process--that's rather what yogurt is all about.
I understand sour cream is made by the same essential process, but I don't know what changes I would need to make. Could I just add a little yogurt to some cream? Do I need to change the ratio of fresh to culture? Does the incubation time or temperature change at all?