Nuoc mam, fish sauce, is the most essential ingredient for everyday meals and cooking in Viet Nam.
It is a signature aspect of Vietnamese cuisine, and distinguishes it from Chinese cooking, which is marked by its prominent use of soy sauce. This inimitable, Vietnamese sauce is obtained through the maceration of saltwater fish and their fermentation under sunny, natural conditions. The ingredients and climate are readily available thanks to the country’s lengthy coastline and tropical forecasts.
The best nuoc mam comes from the islands of Phu Quoc and Cat Hai, respectively on the southwestern and northern coasts, and from the central province of Phan Thiet.
There’s a Thai variation of nuoc mam, but it does not compare to the original Vietnamese product. Nuoc mam is rich in amino acids, sodium chloride, histamines and organic and mineral phosphors.
Nuoc mam may have a strong smell for the uninitiated, but it is no more intense than a Roquefort cheese or a gamy meat. Plus, there are ways to lighten the odour, namely by not using it when cooking over an open fire.
By flavouring it with a variety of condiments, nuoc mam can be used to enhance a number of different dishes. When ginger is added, it is perfect for boiled duck; vinegar, lemon, garlic and onion are added for fried fish; and a smashed, hard-boiled duck egg may be added for boiled cabbage.
Nem, spring rolls, require a very light sauce seasoned simply with vinegar, sugar and pepper, while banh cuon, a plain or stuffed rice wrap, goes particularly well with a wee bit of natural belostomid essence.
In Phan Thiet, home to one of the country’s most famous brands, nuoc mam is garnished with pineapple slices, while house wives in some other parts of the South boast a more exotic recipe: nuoc mam in boiled coconut milk.
But the ingredient that tops all others is chilli, fresh or powdered the hotter the better and lots of it. In addition to nuoc mam, there are paste products, generically named mam, also made from macerated marine fish and crustaceans and believed to have been introduced by the Cham and other ethnic groups of Malayo-Polynesian origin.
The most common of these other products is the shrimp-based mam tom, notorious for its strong smell but irreplaceable in regards to dog meat, pig organs, grilled tofu and fat pork. Mam tom, called mam ruoc in the central regions, is a must-have for certain Hue specialities, such as bun bo, beef noodles, and com hen, mussels with rice.
Still, there’s nothing like mam tom chua, sour fermented shrimp, the crown jewel of Hue cooking. Farmers in the Hong (Red) River Delta have their own special brew, which they make from small, fresh-water shrimp and call mam tep. It’s unforgettable once you’ve tried it with a little fat pork, noodles and some aromatic herbs.