Basic Thai Ingredients
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Chilies come in many shapes and sizes. Fresh finger-length chilies are moderately hot. Tiny red, green or yellow-orange bird's-eye chilies are fiery hot. Dried chilies are usually cut into lengths and soaked in warm water to soften before use.
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Coconut milk can be bought fresh from local wet markets and is also available canned and in packets. It comes in varying consistencies and you will need to adjust the thickness by adding water as needed.
In general, you should add 1 cup of water to 1 cup of canned or packet coconut cream to obtain thick coconut milk, and 2 cups of water to 1 cup of coconut cream to obtain thin coconut milk.
Coriander is an indispensable herb and spice in Thai cooking. Coriander seeds are roasted and then ground in spice pastes. Coriander roots are used in the same way, while coriander leaves (also known as cilantro or Chinese parsley) are used as a herb and a garnish.
Curry powder is a commercial spice blend that generally includes ground cumin seeds, coriander seeds, turmeric root, ginger, cinnamon and cloves. Different combinations vary in color and flavor and are used for different types of curriesmeat, fish or chicken. Use an all-purpose blend if a specific curry powder is not available.
Store curry powder in an air-tight container in the refrigerator.
Dried Chinese sausages, or lap cheong, are perfumed with rose-flavored wine. Generally sold in pairs, these sausages keep without refrigeration and are sliced and cooked with other ingredients rather than eaten on their own. They should not be eaten raw. Substitute any sweet, dried sausage or meat jerkey.
Dried prawns are tiny, orange prawns that have been dried in the sun.
They come in different sizes. Available in Asian markets, they should look orangy-pink and plump; avoid any with a grayish appearance or an unpleasant smell. Dried prawns will keep for several months.
Dried shrimp paste, which is called kapee in Thai and is known as belachan in Singapore and Malaysia, is a dense mixture of fermented ground shrimp that must be toasted before useeither wrapped in foil and dry-roasted in a pan or toasted over a gas flame. It is sold in dried blocks wrapped in paper or plastic in most Asian food stores.
Fish sauce is made from salted, fermented fish or shrimp.
Good quality fish sauce is golden-brown in color and has a salty tang. It is available in bottles in most supermarkets.
Galangal ( lengkuas) is an aromatic root that is similar in appearance to ginger and a member of the same family. It adds a distinct flavor to Thai curries, and most stores now sell it fresh. It can be sliced and kept sealed in the freezer for several months.
Garlic chives or gu cai, also known as Chinese chives, have long, green flat leaves that resemble thin spring onions.
They have a strong garlicky flavor and are added to noodle or stir-fried dishes during the final stages of cooking. If you cannot get them, use spring onions or regular chives.
Kaffir limes are small limes with a very rough and intensely fragrant skin, but virtually no juice. The skin or rind is often grated and used as a seasoning. Fragrant kaffir lime leaves are added whole to soups and curries or finely shredded and added to salads or deep-fried fish cakes, giving a wonderfully tangy taste to these dishes.
Lemongrass is a highly aromatic herb.
Lemongrass is a highly aromatic herb.
The tough outer layers of the stem should be peeled away and only the pale, inner heart of the thick end are used.
Oyster sauce is a flavorful soy-based sauce made with oyster extracta Cantonese specialty. A vegetarian version is available, and is sometimes sold as "mushroom oyster sauce" or "oyster-flavored sauce". If you do not like monosodium glutamate, choose your brand carefully as most are laden with this additive. Oyster sauce is available in most supermarkets. 
Noodles are a universal favorite in Thailand. 
Noodles are a universal favorite in Thailand.
Fresh yellow wheat noodles are thick, spaghetti-like noodles made from wheat flour and egg. Substitute fresh spaghetti or fettucini if you cannot find them. Dried rice vermicelli (mifen or beehoon) are very fine rice threads that must be plunged into hot water to soften before use. Rice stick noodles (also known as "river noodles", kway teow or hofun) are wide, flat rice noodles sold fresh in Asian markets. If not available, use dried rice stick noodles instead. Glass noodles, also known as cellophane or bean thread noodles, are thin, clear strands made from mung bean starch and water.
They are sold in dried form and must be soaked in warm water for 15 minutes to soften.
Palm sugar is made from the distilled juice of various palm fruits and varies in color from golden to dark brown. It has a rich flavor similar to dark brown sugar or maple syrup, which make good substitutes. Plum sauce is a sweet sauce made from plums, vinegar, sugar and a dash of chilies. It is sold in jars or cans in the supermarket. 