From: e. in SF (eosuna@hamquist.com) Hi Jerome . . . here's a recipe for creme fraiche and an idea for substitutions . . . Creme Fraiche is very similar to sour cream -- depending on whether the dish is hot or cold you can substitute that. If the dish is cold they are interchangable. If the dish is hot, like if you're supposed to swirl it in a hot soup or add it as a component to any simmering dish, sour cream will separate and curdle. Here is a recipe for creme fraiche as it is really fabulous!1 tsp. buttermilk1 cup whipping cream (if you can find some that's not ultra-pasteurized it's best)Stir the buttermilk into the cream and heat to lukewarm. Pour the mixture into a loosely covered jar and let stand at room temp (not over 85F or under 60F) until thickened. It can take 8 hours on a warm day and up to 24 to 36 on a cold day.