This is an edible chrysanthemum leaves known as tung ho (in cantonese) locally. It is also known as Shingiku in Japanese. There are two types: small leaf tung ho or broad leaf tung ho. The one I bought is the broad leaf type where it is more rounded and has larger leaves.
It has a strong herby, bitter and peppery flavour. Piglet commented that it taste like parsley. I love drinking chrysanthemum tea but the leaves just taste different. I suppose it is an acquired taste.
It can be used in stir fries or soups, hot pot or even eaten raw. I tried stir frying it with garlic just to gauge the flavour.
Maybe I might try it in soups the next round or even as a coriander or parsley substitute.