This recipe produces a crème fraîche reminiscent of the enchanting varieties found in France. I prefer it to any of the commercial products available here. The proportion of one tablespoon of buttermilk to one cup of heavy cream results in a fresh, creamy taste with a gentle tang. Crème fraîche is wonderful for finishing sauces because, unlike sour cream, it does not curdle with heat.
Combine the cream and buttermilk in a jar with a tight-fitting lid and place it in a warm spot, such as the top of the refrigerator or near the stove. Allow to sit undisturbed for 12 to 14 hours or until thickeped but still pourable. (Ultrapasteurized cream may take as long as 36 hours to thicken.)
© 1992 Rose Levy Beranbaum. All rights reserved.