It doesn’t curdle and separate when you heat it.
Homemade Crème Fraiche
Mix together and leave in a warm spot (about 70-75 degrees F.) for 24 hours, or until thick.
Refrigerate for 24 hours before using.
Should last a week or two.
Be sure to get your hands on the best, freshest cream you can find.
In the supermarket you'll want to look for "pasteurised," not "ultra-pasteurised" heavy whipping cream.
Also, be sure to use cultured buttermilk otherwise you’re going to be waiting a full day to see nothing happen.
By blogger, Chef John.