Ingredients

This is by no means an exhaustive list (or even a slightly austive list, if I'm honest). Just a few scribbled notes on ingredients that frequently turn up in my recipes:

fish sauce Also known as: nuoc nam (Vietnamese) nam pla (Thai)	An essential flavouring in Vietnamese and Thai cooking, fish sauce is made from salted, fermented fish (or occasionally shrimp). It has a very pungent odour when raw, which softens when cooked, and adds depth of flavour and saltiness to dishes. There is no real substitute that adds the same flavour, although vegetarians will often use soy sauce instead. Can be bought in all good supermarkets and will keep well in the fridge.
galangal Also known as: krachai (Thai) Laos powder (when ground)	Pinkish rhizome, similar in taste and preparation to ginger. Can be bought as fresh roots in Asian supermarkets, or bought in jars (already minced, for immediate use). The powdered form (Laos) tastes very different, and as such as not a good substitute for fresh. If you cannot find galangal, substitute ginger.
palm sugar also known as: jaggery gula merah	Raw brown sugar, commonly made from the sago palm, sold in tubs or blocks from Asian shops. Can substitute light brown sugar if necessary.
sambal olek	Paste made from minced chillies, with salt added as a preservative (and sometimes a little sugar). Bought in jars and stored in the fridge, it makes a convenient substitute for fresh chillies.
shrimp paste Also known as: balachan or belacan (Malay) terasi (Indonesian) kapi (Thai)	Another essential flavour in SE Asia, it's made from salted and fermented shrimp. Bought in jars, blocks or tubs, it will keep a long time. Different brands have different moisture contents - the drier preparations will last longer. The pungent odour softens on cooking. There is no substitute.
water spinach Also known as: morning glory ung choi phak bung (Thai) kangkung (Malay)	A very popular green, leafy vegetable, most commonly used in stir fries.