Specially for the basic galley and lazy on-board cook! The chewy-crispy result is best by using butter and white sugar, but I've used uncoloured golden sugar, and margarine - and even wholemeal flour, but that makes it much heavier. You can also do without the chocolate chunks, or without the nuts, and even without both if you're desperate! Use whatever is in your galley cupboards - add glace cherries, or raisins, instead. Be imaginative! - But the best results come as below.