For the Ginger Passionfruit Trifle what is the closest equivalent of the green ginger wine? I don't think we have it here in Sydney. I would be happy to use another alcoholic drink, but have never seen a ginger one. Perhaps I can use ginger cordial syrup, dilute it with water and then mix in some brandy or rum to make up a total of the recommended amount of liquid? I think that would work well in the Trifle recipe. Thanks!
Nigella's Ginger Passionfruit Trifle (from Nigella Express and on the Nigella website) gets its ginger element from ginger wine. Ginger wine is a fortified wine made with root ginger. Stone's and Crabbie's are the two best-known brands and you may find the ginger wine just listed under one of the brand names, rather than as ginger wine.
If you can't find the ginger wine then your alternative of ginger cordial/syrup, slightly diluted and mixed with a spirit would be a good one. Ginger wine is often mixed with whisky to make a "Whisky Mac", so whisky may be one to try (though mix the two carefully, making sure that the whisky flavour is not too dominant). Alternaively the undiluted cordial could be mixed direct with a different fortified wine such as Madiera or Marsala.
Ginger cordial is sadly not available everywhere so another alternative could be to use ginger beer mixed with a spirit. Again taste and adjust the ratios of spirit to ginger beer according to your own taste.