LEMONGRASS: Although lemon grass is central to Asian cuisine, especially Thai, it works well in Western dishes, too. This mixing of flavours is sometimes called 'fusion'. Also called citronella or sereh, it grows in dense clumps, from which the individual stems are cut. Lemongrass look a little like fat spring onions, with the same swollen base, but the stalk is woodier, and composed of tightly packed grey-green leaves. The fragrance and flavour is unique - lemony, but sweet - and is quite subtle until the stalk is cut or bashed. PREPARE IT: You can use lemongrass whole, sliced or pounded to a paste. To use whole, slice off the very bottom of the stalk, and peel off any dried-out layers, then bash the woody top end with a rolling pin to soften, and help release some of the aromatic oils. Whole freeze-dried lemon grass can be prepared in the same way. For chopping or pounding, only the bottom seven or eight centimetres are edible - slice off and discard the rest. Then chop finely or pound to a pulp in a pestle and mortar. STORE IT: Stored wrapped, in the fridge, fresh lemon grass will keep for a couple of weeks. Freeze-dried whole lemon grass should be kept wrapped up, in a cool, dark place. COOK IT: Use whole lemon grass in stews and curries (remember to fish it out before serving). Chop and use to make marinades and soups or add to stir-fries. Use as a flavouring for crème brulee or steep a stalk in a bottle of vodka for cocktails (clean and bruise a lemon grass stalk, then put it in a nearly full bottle of vodka for 3-4 days, shaking occasionally; then remove the stalks.