Lemon grass has variety of uses in cooking such as base for curries, soups and stews, as flavoring for salads and as stuffing ingredient for roasted chicken, turkey or pig.

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"Tanglad or Lemongrass (Cymboporon citratus) is a fragrant grass that grows in abundant clumps just about anywhere in the tropics. It possesses a larger bulb near the base of the stalks and it tanglad is here that the lemon or citrus flavoring is most often obtained (though we Filipinos use the entire leaf for stuffing). We used to have a huge healthy plant at home in my kitchen garden but for some reason it died last year. So I have taken to purchasing our tanglad at the markets instead. Lemongrass is used as a base for curries, soups and stews and it is also used to flavor salads, as part of marinades and as stuffing material. It can be infused into hot water for a simple herbal infusion and it now flavors desserts as well."

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Lemon grass is used in cooking because of its flavoring and aromatic color. It adds taste to the fish, beef, pork, & chicken soups. It is also added to curries and other dishes.
It can also be pounded and to make a paste and use it as a marinade for and stir-fry dishes.

This lemon grass is used in cooking for its aromatic flavour like that of a lemon.It normally goes very well with garlic and seafoods. Lemon grass tea is very common. Apart from this it helps in digestion and intake of lemon grass tea helps relieve headaches.

For further ref: http://www.gourmetsleuth.com/lemongrass.htm

lemon grass tea and soups with lemon grass tastes good.