It couldn't be simpler to make Crème Fraîche at home using two simple ingredients. Not only is making creme fraiche a fun project, but it's economical, too, since creme fraiche is an expensive store-bought specialty item. You can also customize it to how you like it in terms of tanginess by adding up to 1 additional tablespoon of buttermilk to the cream.
Make sure to start with clean utensils to prevent any growth of any lingering bad bacteria. Wash all equipment with warm soapy water, or run in the dishwasher.
Don't use ultra-pasteurized milk. The cream is heated to a very high temperature and can possibly prevent the creme fraiche from fermenting.
For a tangier creme fraiche, add 3 tablespoons of cultured buttermilk.
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