Ok so I've plumped with Delia over Nigella, mainly because I have a very good quality 20cm tin and Nigella doesn't have a breakdown for 20cm.
I wanted to ask about cooking time though, Delia says 4hrs at gas mark 2, but Nigella's doesn't say that until you get to the big 25cm tin, I'm a novice at all this, can someone please guide me.
Nigella has 2.5 hrs for an 18cm tin and 3.5 hrs for a 23cm tin, so comparing those Delia's seems like a loooong cooking time.