Creme fraiche is simply amazing. And, it is easier than easy to make. There is just one tiny detail to pay attention to.
Creme fraiche (fresh or new cream in French) is a soured cream that is not as sour as regular sour cream, but has a similar texture. It is made by combining fresh cream with some buttermilk and letting it sit for 24 hours at room temperature before refrigerating. The secret is this: you cannot use ultra-pasteurized cream. While ultra-pasteurized cream is the most commonly found in grocery stores, it has been treated to the point where none of the natural bacteria and enzymes of the cream remain, so it cannot react to the cultures in the buttermilk to make a cream.
Instead, get a pint of farm fresh cream from your local specialty cheese shop or dairy goods store. The one I used was from a local farm in New York and was pasteurized at the lowest temperature possible, or so it was claimed on the label.
In a glass jar, combine 1/2 pint heavy cream with 2 tablespoons buttermilk with active cultures. Put the lid on the jar and let it sit out for 24 hours on the counter. Then, into the fridge it goes. When chilled, you have creme fraiche.
For the carnitas recipe, I added some lime zest and fresh grated ginger to the creme fraiche before adding a nice spoonful to the dish.