Cream Fraiche or Sour Cream

[Guest guest]

I want to make creme fraiche as a topping for my chicken enchiladas. For

years I would make it by stirring some commercial buttermilk into some store-

bought cream and letting it sit in the windowsill for 24 hours, then

refrigerating

it-I felt very European! Well now, I don't usually buy commercial buttermilk

because I can use sour milk or kefir for pancakes. So what do I use to make

creme fraiche? I will probably end up experimenting, but since I only bought a

pint of cream this time, I would like to be assured of something working so that

I don't waste it!

Kathy

P.S. I also have kefir whey. Would that be likely to work the best?