In the Vanilla Fudge recipe, it says condensed milk, is it the sweetened condensed or unsweetened? And is the granulated sugar caster sugar or just the normal type of granulated sugar?
Nigella's Vanilla Fudge is a traditional recipe that uses condensed milk. In the UK condensed milk is always sweetened, though in some countries it may be labelled as "sweetened condensed milk" and it is the sweetened type that should be used. Unsweetened condensed milk is usually labelled as "evaporated milk".
In this recipe Nigella uses regular granulated white sugar, it does not need to be caster sugar. However you should make sure that the sugar is completely dissolved before the mixture boils and this can take a little longer with British granulated sugar. So in the UK you could use caster sugar if you prefer. Outside of the UK granulated sugar tends to be finer so is the best one to use to make the fudge.