For the few above who seem confused, creme fraiche, is a cultured cream, or sour cream, and Mexican cream is a mixture of Sour cream and whole cream(with a bit of lime). Neither are a fit substitute for clotted cream, though in their own element, are fine, indeed. Though it is possible to make clotted cream in the US, the fat content of our milk is significantly lower, so it falls far short of the authentic stuff--