Crispy 'seaweed' is a clever invention of Chinese restaurateurs, who took tough and often unusable dark green cabbage and kale leaves, then shredded and fried them to make a snack so well-loved it's now a core part of any Chinese restaurant's mixed starter dish. The look, texture and flavour is indeed very similar to actual seaweed dishes found in East Asia, just more widely available in the UK (and much cheaper)!