I grew up eating Korean, Japanese, and Chinese food, but it wasn't until college that I experienced Thai and Vietnamese cooking. Once I started, I couldn't get enough of these cuisines. The dishes had an incredible richness and savor that I couldn't identify, but whatever it was, it made me want to keep eating.
Finally, a friend helped identify the source of all that mouth-watering umami flavor: fish sauce. She even bought me a bottle of my very own, and once I cracked open the lid and got a whiff of that pungent, salty, mouth-watering liquid within, I started adding it to everything I ate.
Potatoes. Spring rolls. Soup. Stir-fries. Salad dressings. Marinades. Fish sauce improved almost every single thing I used it in (except chili, where it just tasted weird). If I ate at a Vietnamese or Thai place, I always asked my server to bring extra fish sauce so I could splash it all over my entrees.
Called nam pla in Thailand and nuoc mam in Vietnam, fish sauces are made by salting and fermenting fish, and then adding water, salt, and a touch of sugar for contrast. Occasionally pepper or citrus are added, too. It can be made from salt or freshwater fish.
Fish sauce is an amazing addition to just about any savory dish, not just Asian ones. Much like Marmite, it's an "umami bomb" that will give depth and richness to sauces and main courses. Some chefs use it in fried chicken, mignonette, and to balance out bitter vegetables. I like to add it to my chicken stock. Bon Appétit does, too, and they add it to a whole slew of other, non-Asian dishes as well.
If you're new to fish sauce or haven't tried Thai or Vietnamese food, then you might want to start off with Worcestershire sauce, which contains anchovies as one of its main ingredients. I like to think of it as fish sauce's milder, slightly less interesting cousin.
"High-quality fish sauce, which is the first to be drained off the fermented fish, is usually pale amber, with a more delicate and balanced flavor; premium-grade fish sauce, such as Three Crabs or Phu Quoc brands, are best in dipping sauces. For cooking, stronger-flavored, lower-grade brands, such as Squid or Tiparos, which are made from a secondary draining, work fine. Fish sauces bottled in glass taste better and last longer than those packaged in plastic."
If you're brand new to fish sauce, then you might want to check out the taste test Our Daily Brine conducted. They give a good rundown on the qualities to look for in fish sauce and tell you which kinds fared best with their judges. The Kitchn also has a guide on how to read fish sauce labels and what qualities a good fish sauce should have.
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