How to Make Creme Fraiche. Creme fraiche is a thick, rich cream that is cultured and unpasteurized to give it a slightly tart flavor. Used much like sour cream, creme fraiche is not as thick, has a higher butterfat content and is used more frequently as an accompaniment to desserts. Making creme fraiche isn't difficult, but it does take time, so plan ahead. Follow these steps and add an elegant touch to desserts.
Measure 2 tbs. of buttermilk into a small dish. Let it sit in a draft-free space to come to room temperature or at least 75 degrees F.
Heat 1 cup of heavy (whipping) cream over very low heat to body temperature. Do not to exceed 100 degrees F. Remove from the heat.
Pour the cream into a glass jar or glass bowl. Add the 2 tbs. of buttermilk. Stir once or twice with a wooden spoon. Seal the jar or cover the bowl with its lid.
Keep the mixture in a warm place (at least 75 degrees F) for 12-36 hours until thickens, depending on the consistency of the temperature. Set the container in a pan of warm water if the room is drafty or cool. Change the water periodically.
Stir the thickened creme fraiche. Cover and refrigerate for up to 10 days.
Serve with fruit or sweet desserts. Add a touch of sugar before serving, if desired.