Try it: Fish sauce is an indispensable ingredient in southeast Asian cooking. This amber-colored liquid has a very pungent, fishy aroma that is moderated with cooking. The sauce is made by salting and fermenting fish, usually anchovies, and draining off the liquid. Some fish sauce brands contain sugar as well.

Use it: Fish sauce is called for in all manner of Thai, Vietnamese, Cambodian, Laotian and Filipino dishes. Just like olive oil, it is sold in varying degrees of quality. Though saltiness varies from brand to brand, Jeffrey Alford and Naomi Duguid, authors of Hot Sour Salty Sweet, note that 1 tablespoon of fish sauce is roughly equivalent to 1 teaspoon of salt.

Buy it: Fish sauce is inexpensive, often costing less than $3 at Asian markets. It should appear clear, not cloudy. It is available not only in Asian markets but also specialty stores and larger supermarkets. Fish sauce is called nam pla in Thai, nuoc nam in Vietnamese, patis in Filipino. Store in a dark cool place; it lasts indefinitely.