Sawtooth coriander

Leaf, stem and root of the same plant — citrusy, green and, to some people, soapy.

What to do with it

Classics built on it

YunnanDai lemongrass grilled fishA river fish split open, stuffed with chopped herbs, garlic and chilli, bound up with lemongrass stalks and grilled over charcoal.No one here has made it yet

Kinds

Leaves and stems: Stems have more flavour than leaves; chop them in.
Roots: Pounded into Thai pastes.
Seeds: A different spice altogether: warm and orangey.

Knowing it

Where to buy: Big bunches from Asian, Middle Eastern or Latin American grocers, roots on if you can.
A little history: The 'soapy' taste is partly genetic — a variant near an olfactory receptor gene makes some people notice it far more.

Kitchens that keep it in

Yunnan province, south-western ChinaYunnanA kitchen of many peoples, from the edge of the Tibetan plateau down to the tropics: rice noodles and cured ham, wild mushrooms and fresh cheese, and the sour, herb-bright cooking of the Dai.7 classics