Most gourmets would agree that the best food available to man is the salt and vinegar chip. The combination of crunch, vinegary bite and salty tang is unbeatable. But the chip aficionados among you will have noticed that premium brands are not satisfied with humble flavours. Simple labels are being replaced with grandiose. No longer salt and vinegar, but sea salt and balsamic vinegar; not cheese and onion, but mature Devonshire Cheddar and caramelised red onion; not prawn cocktail, but hand cooked Scottish langoustines with dill and lemon.