Making Crème Fraîche

All mass-produced cream is pasteurized ... crème fraîche is pasteurized cream which has had lactic acid and other natural fermentation agents that have been killed by pasteurization put back. Initially the crème fraîche is the consistency of double cream but, as it ages, it thickens and stiffens, while acquiring a sharp, almost cheesy, taste.

You can make it yourself by putting