Where in the States can I find fleur de sel for the Salted Caramel Sauce? I have looked in most of the big grocery stores and no-one carries it.
Nigella's Salted Caramel Sauce is an easy version of a caramel sauce that is flavoured with fleur de sel. Fleur de sel is a salt made from evaporated sea water and tends to come in coarser, irregular grains than fine or table salt. It also tends to be slightly moister than regular table salt. It may be labelled as "flor de sal" if it is from Spain or Portugal and some of the best known French versions are sel de Guerande and sel de Carmague. Cornish sea salt is a British alternative and is available in some US supermarkets. Maldon salt is a more flaky version of fleur de sel and can be used as an alternative. It is also available in some larger US supermarkets. Several versions of fleur de sel are available on-line and it is a good salt to use for finishing dishes.
Otherwise you could use kosher salt or fine sea salt, though you may need to use these in smaller quantities as they can measure differently by volume. The recipe suggests adding salt to your own taste, so let the sauce cool enough that you can taste it then add the salt a little at a time and taste between each addition.